David Anthony Kost and Timothy John O’Meara were convicted in a jury trial of conspiring to possess cocaine with intent to distribute, in violation of 21 U.S.C. §§ 841(a)(1) and 846. Both O’Meara and Kost challenge their convictions and the district court’s^[1] sentences. We affirm.

I.

Based upon information he had received that Kost was involved in distributing cocaine, Hennepin County Deputy Sheriff Jeffrey Burchett, an undercover drug agent, contacted Kost on March 2, 1988, and attempted to purchase five kilograms of cocaine from him. Kost and Burchett did not reach a final agreement on the sale. On March 31, 1988, Kost asked Burchett if he could buy two ounces of cocaine from him. By April 4, Kost had increased his desired purchase to six ounces of cocaine, agreeing to pay $1,000 per ounce.

Kost and Burchett agreed to meet in Minneapolis on April 5, 1988, to complete the sale. O’Meara accompanied Kost to Minneapolis. Kost and Burchett met alone in Burchett’s automobile in a parking lot while O’Meara waited in another car. Other undercover agents were stationed nearby. Burchett wore a body transmitter that enabled the other agents to record the conversation via radio link. Before the sale took place, Burchett told Kost that he had eight ounces of cocaine that he preferred not to break up. Burchett agreed to “front” the additional two ounces to Kost, meaning that Kost could take the additional two ounces of cocaine without paying for it immediately. Kost paid Burchett $1,000 and told him that O’Meara would pay the remaining $5,000. Burchett testified that Kost planned to tell O’Meara that the cocaine was $1,250 an ounce, instead of $1,000 an ounce, so that O’Meara would get four ounces for $5,000 and Kost would make a profit from the sale to O’Meara.

Kost summoned O’Meara to Burchett’s car to deliver the money. (The recording[*1218] tape ran out at this point, but the other agents were able to hear the conversation with O’Meara via the radio transmitter.) Burchett said that he wanted to see the money before he handed over the cocaine. O’Meara gave Burchett $5,000. In return, Burchett handed O’Meara a zip-lock bag containing approximately eight ounces of cocaine. O’Meara tasted the cocaine, pronounced it to be of good quality, and passed the bag to Kost. Burchett then asked O’Meara what cocaine sold for in the Detroit Lakes, Minnesota, area where O’Meara lived. O’Meara responded that cocaine sold for about $2,000 an ounce when “cut one quarter,” meaning when diluted by 25 percent. On signal from Bur-chett, the other agents then moved in and arrested Kost and O’Meara.

The district court denied O’Meara’s motions to sever his trial from Kost’s. O’Meara objected throughout the trial to testimony concerning Kost’s negotiations to purchase cocaine from sources in Arizona for Burchett. The district court also denied O’Meara’s request to instruct the jury on conspiracy to possess cocaine as a lesser included offense.

Kost testified regarding his negotiations with Burchett and his intent to keep some of the cocaine and to sell the remainder. Kost also testified that O’Meara had no knowledge of the drug transaction, claiming that O’Meara had accompanied Kost to the April 5 meeting with Burchett because Kost had asked for O’Meara’s assistance in repaying a gambling debt.

Before sentencing, Kost continued to claim to a probation officer that O’Meara knew nothing about the drug transaction. O’Meara admitted to the probation officer, however, that he was knowingly involved in orchestrating the drug purchase.

The district court sentenced O’Meara under the Federal Sentencing Guidelines (Guidelines) to 33 months’ imprisonment, followed by three years’ supervised release. The court based its sentence on a total offense level of 16, calculated by taking into account O’Meara’s criminal history score, the eight ounces of cocaine involved in the transaction, a two-point reduction for acceptance of responsibility, and another two-point reduction for O’Meara’s minor role in the transaction. The court sentenced Kost to 57 months’ imprisonment, based on a total offense level of 24, arrived at from a base offense level of 20, plus a two-point upward adjustment for acting as an organizer and leader in the crime and a two point upward adjustment for obstructing justice.

II.

Kost challenges his conviction on the ground that O’Meara’s conviction is invalid. If O’Meara’s conviction cannot stand, asserts Kost, neither can his own conspiracy conviction since O’Meara was his only conspirator.

O’Meara raises a number of challenges to his conviction, including the district court’s refusal to grant his motions to sever his trial from Kost’s. He alleges that the district court admitted hearsay evidence of statements Kost made in negotiations with Burchett prior to the April 5, 1988, meeting which are not admissible as the declarations of a co-conspirator under Fed.R.Evid. 801(d)(2)(E) and which the district court admitted without following the procedures set forth in United States v. Bell, 573 F.2d 1040 (8th Cir.1978). O’Meara asserts that there is no evidence to suggest that O’Meara and Kost were engaged in a conspiracy except for the day O’Meara accompanied Kost to Minneapolis to close the deal with Burchett. Thus, Kost’s statements made when negotiating with Burchett were inadmissible under the co-conspirator exception because Kost did not make the statements in the course of and in furtherance of a conspiracy. O’Meara contends that he suffered prejudice as a result of these erroneous rulings.

Persons charged with a conspiracy will generally be tried together, especially where proof of the charges against each of the defendants is based on the same evidence and acts. United States v. Voss, 787 F.2d 393, 401 (8th Cir.), cert. denied, 479 U.S. 888, 107 S.Ct. 286, 93 L.Ed.2d 261 (1986); United States v. Singer, 732 F.2d[*1219] 631 (8th Cir.1984). We will not disturb a district court’s denial of a severance motion in the absence of a showing that the court abused its discretion, causing clear prejudice to a defendant’s right to a fair trial, Singer, 732 F.2d at 634, or, as stated in Voss, 787 F.2d at 401, “real” prejudice (a term we consider synonymous with “clear”). The denial of a severance motion results in clear prejudice when the defendant is deprived of an appreciable chance that he would not have been convicted in a separate trial, and not merely when he would have had a better chance for acquittal in a separate trial. Singer, 732 F.2d at 635. Disparity in the evidence introduced against each of the defendants, or allegations that evidence which incriminated a co-defendant had a “spillover” prejudicial effect against the defendant, are insufficient grounds for severance unless the district court in its discretion determines that the defendant has demonstrated the jury’s inability to “compartmentalize” the evidence against the separate defendants. Id.; United States v. Andrade, 788 F.2d 521, 530 (8th Cir.), cert. denied, 479 U.S. 963, 107 S.Ct. 462, 93 L.Ed.2d 408 (1986); United States v. Milham, 590 F.2d 717, 722 (8th Cir.1979). Moreover, we will not reverse for failure to follow the procedures established in Bell absent a showing of prejudice. United States v. Mason, 869 F.2d 414, 416 (8th Cir.), cert. denied, — U.S. —, 109 S.Ct. 3219, 106 L.Ed.2d 569 (1989); see also United States v. Cerone, 830 F.2d 938, 952 (8th Cir.1987), cert. denied, 486 U.S. 1006, 108 S.Ct. 1730, 100 L.Ed.2d 194 (1988).

We see no prejudice to O’Meara from the district court’s rulings. The evidence concerning Kost’s negotiations with Arizona cocaine suppliers did not mention O’Meara at any point. The prosecution acknowledged before the jury that the evidence of Kost’s preliminary negotiations with Bur-chett related only to Kost. Although the district court denied O’Meara’s initial request for an instruction, the court later instructed the jury that any reference to the Arizona transaction “should not be considered as against the other defendant, Mr. O’Meara, but only as against Mr. Kost,” when it became clear that there was no connection between the Arizona transaction and O’Meara. The court so instructed the jury again immediately before its deliberations.

We see no difficulty that the jury might have had in compartmentalizing this evidence in light of the court’s clear instructions and the absence of any involvement by O’Meara or reference to him in the negotiations. A jury is capable of compartmentalizing evidence in a case such as this where the trial took only three days, did not involve complex issues, and involved only two defendants and only one count against each. See United States v. Davis, 882 F.2d 1334, 1340 (8th Cir.), petition for cert. filed, 1989 WL 163316 (1989); United States v. O’Connell, 841 F.2d 1408, 1432 (8th Cir.1988), cert. denied, — U.S. -, 109 S.Ct. 799, 102 L.Ed.2d 790 (1989). As the government argues, if anything the joint trial should have been beneficial to O’Meara. Had the jury believed Kost’s testimony, it would have exonerated O’Meara.

O’Meara also challenges his conviction on the ground that the district court erred by refusing to instruct the jury on conspiracy to possess cocaine as a lesser included offense of conspiracy to possess with intent to distribute. A “defendant is entitled to an instruction on a lesser included offense if the evidence would permit a jury rationally to find him guilty of the lesser offense and acquit him of the greater.” Keeble v. United States, 412 U.S. 205, 208, 93 S.Ct. 1993, 1995, 36 L.Ed.2d 844 (1973). A trial court should give lesser included offense instructions when, among other factors, there is evidence that would support conviction of the lesser offense and the proof on the element or elements differentiating the two crimes is sufficiently disputed so that the jury could consistently acquit on the greater offense and convict on the lesser. United States v. Roy, 843 F.2d 305, 310 (8th Cir.), cert. denied, 487 U.S. 1222, 108 S.Ct. 2881, 101 L.Ed.2d 916 (1988).

O’Meara’s defense at trial was that he was unaware of the drug transaction. The[*1220] material evidence of O’Meara’s involvement was testimony concerning the conversation in the car the day of the transaction, when O’Meara discussed in detail how he would sell cocaine. There was no evidence offered indicating that O’Meara’s involvement in the purchase plan was for the sake of his personal use. Therefore, the district court did not err in concluding that O’Meara was not entitled to a lesser included offense instruction.

We have carefully considered O’Meara’s contention that the evidence was insufficient to support his conviction, as well as his contention that his statements to Bur-chett in the car should not have been admitted because the agents failed to record the entire conversation, and find that these contentions are without merit. Therefore, we uphold O’Meara’s conviction and, consequently, Kost’s conviction as well.

III.

Both Kost and O’Meara challenge the propriety of their sentences. Kost raises a number of objections to the district court’s application of the Guidelines, including the upward adjustment in his offense level for acting as an organizer or leader, the upward adjustment for obstructing justice, and the district court’s refusal to lower his offense level for acceptance of responsibility.

When reviewing sentences imposed by the district court, we accept the court’s findings of fact unless clearly erroneous and give due deference to the court’s application of the Guidelines. 18 U.S.C. § 3742(e).

The district court noted that with an upward adjustment for a role as an organizer or leader, Kost fell within a sentencing range of 57 to 71 months. Without the upward adjustment, Kost would fall within a sentencing range of 46 to 57 months. The district court sentenced Kost to 57 months, finding further consideration of whether Kost acted as an organizer or leader unnecessary. Because Kost’s sentence fell within a range subject to the court’s discretion, we agree that the issue is moot.

As for the obstruction of justice adjustment, Kost claims that the district court unfairly concluded that he had lied during trial and to the probation officer when he claimed that O’Meara was unaware of the cocaine transaction on April 5. Kost contends that a sentencing court cannot justly put a defendant in the position of choosing between either telling a different story after conviction in the hopes of lenity at sentencing or admitting perjury.

The crux of the issue here, however, lies in O’Meara’s confession to the probation officer of his knowing involvement in the cocaine deal. The district court did not base its conclusion on Kost’s conviction but on O’Meara’s confession. The validity of the district court’s reasoning is supported by our recent decision in United States v. Wagner, 884 F.2d 1090 (8th Cir.1989), in which we held that an upward adjustment for obstruction of justice could be based on the district court’s determination that the defendant lied at trial because the testimony of law enforcement officers contradicted the defendant’s testimony. Id. at 1098. We therefore find that the district court justifiably increased Kost’s sentence for obstructing justice.

Because Application Note 4 of the commentary to section 3E1.1 of the Guidelines precludes a downward adjustment for acceptance of responsibility when a defendant obstructs justice, we do not further consider Kost’s position that he was entitled to a reduction.

Finally, both O’Meara and Kost contend that the district court should have sentenced them on the basis of six ounces of cocaine instead of eight ounces. Kost claims that it was fundamentally unfair and a usurpation of the judicial function for police officers to increase, in effect, a defendant’s sentence in an undercover police operation by fronting drugs. The record shows, however, that the negotiations leading to Kost’s acceptance of the additional two ounces did not materially differ from the negotiations preceding the April 5th meeting in which Burchett agreed to sell Kost six ounces of cocaine. Burchett first[*1221] mentioned the additional two ounces in the following part of the April 5th meeting with Kost:

Burchett: “I got eight here. If I gotta break it up, I’ll break it, but you guys got — have anymore case with you at all or what?”

Kost: “No I don’t.”

Burchett: “When’s the next time you’re coming down.”

Kost: “Oh God, let me think. For a thousand an ounce. All you need is another two grand.”

Burchett: “Yep. Really you know this is the best stuff the guy has given me in six months. The other stuff — ”

Kost: “If it’s that good, if you want to front it to me, I can handle it in a week.”

Burchett: “A week? Two grand?”

Kost: “Yep.”

This exchange shows that Burchett simply let Kost know that more cocaine was available. The conversation also reveals that Kost was receptive to the possibility of acquiring another two ounces. Thus, this part of the transaction is not legally distinguishable from the rest of the undercover police operation. Accordingly, the district court did not err in sentencing Kost on the basis of the full eight ounces.

O’Meara asserts that he should not have been sentenced for eight ounces of cocaine because Kost agreed to purchase the additional two ounces without O’Meara’s knowledge. O’Meara points to the distinction between the law governing convictions for conspiracy, which allows a jury to convict a defendant, shown to belong to a conspiracy, for “substantive crimes committed by coconspirators in furtherance of the conspiracy, even though the defendant did not participate in the substantive offense,” United States v. Garcia, 785 F.2d 214, 225 (8th Cir.), cert. denied, 475 U.S. 1143, 106 S.Ct. 1797, 90 L.Ed.2d 342 (1986), and the rules for sentencing. O’Meara cites Application Note 1 to section 2D1.4 of the Guidelines, which at the time he was sentenced read:

If the defendant is convicted of a conspiracy, the sentence should be imposed only on the basis of the defendant’s conduct or the conduct of eo-eonspirators in furtherance of the conspiracy that was known to the defendant or was reasonably foreseeable.^[2]

The language of this comment is an indication that the Guidelines intend to depart to some extent from the common law rule holding conspirators responsible for actions of co-conspirators of which they are unaware. The evidence in O’Meara’s case, however, shows that he willingly accepted the eight ounce bag of cocaine when Deputy Burchett offered it for inspection. O’Meara did not question its weight or verify that he and Kost were purchasing only six ounces. O’Meara has not persuaded us that it was unforeseeable that Kost, as his co-conspirator, would accept an additional two ounces if offered to him. On these facts, we find that the district court’s decision to sentence O’Meara on the basis of eight ounces of cocaine is not clearly erroneous.

Accordingly, we affirm the judgments and sentences of the district court in all respects.