United States Court of Appeals
                             FOR THE EIGHTH CIRCUIT
                                    ___________

                                    No. 97-2485
                                    ___________

United States of America,                *
                                         *
             Appellee,                   *
                                         * Appeal from the United States
      v.                                 * District Court for the
                                         * Northern District of Iowa.
Larry Alan Wilson,                       *     [UNPUBLISHED]
                                         *
             Appellant.                  *
                                    ___________

                            Submitted: September 8, 1998

                                Filed: September 11, 1998
                                    ___________

Before BOWMAN, Chief Judge, WOLLMAN, and LOKEN, Circuit Judges.
                             ___________

PER CURIAM.

        Larry Alan Wilson pleaded guilty to conspiring to distribute and to possess with
intent to distribute 100 grams or more of methamphetamine, in violation of 21 U.S.C.
§§ 841(a)(1), 841(b)(1)(A), and 846, but disputed the ending date of the conspiracy
charged by the government. Specifically, the government charged that Wilson&s
involvement in the conspiracy began in December 1993 and ended in May 1994, while
Wilson contended that his involvement ended when he was incarcerated for a prior
felony drug offense on February 28, 1994. The district court1 found that Wilson&s
involvement in the conspiracy continued after he was incarcerated and that, based on
the prior drug offense, Wilson faced a 20-year mandatory minimum sentence under 21
U.S.C. § 841(b)(1)(A)(viii). The court imposed the 20-year sentence to run
concurrently with the 172-month sentence that Wilson was serving for the prior drug
conviction, but with no credit for time served to date, and five years& supervised
release. After appellate counsel moved to withdraw pursuant to Anders v. California,

(1967), we granted Wilson permission to file a pro se supplemental brief,
and he has done so. We now affirm.

       Wilson first challenges the district court&s conclusion that he committed the
instant offense after a prior felony drug offense had become final; in particular, he
challenges the court&s finding at sentencing that the conspiracy continued after Wilson&s
incarceration. Wilson&s co-conspirators testified at his sentencing, however, that before
Wilson went to prison, he initiated the framework for future drug transactions involving
Wilson&s California supplier and others, and then--from prison--monitored the arrival
of packages, offered advice on how to escape detection, and profited from the
conspiracy through his supplier&s action in setting aside money for him from the
transactions. We thus find the district court did not clearly err. See United States v.
Wayne, 

, 1196-97 (8th Cir. 1990) (standard of review).

       Wilson also challenges the district court&s finding that more than 100 grams of
methamphetamine were involved in the instant offense, and contends that there is no
evidence that the methamphetamine involved was d-methamphetamine. These
arguments fail. The record amply supports the district court&s drug quantity finding.
Moreover, the statute does not differentiate between d- and l-methamphetamine, and
in any event, the methamphetamine upon which the court based Wilson&s sentence was


      1
      The Honorable Michael J. Melloy, Chief Judge, United States District Court for
the Northern District of Iowa.

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identified in a laboratory report received into evidence as d-methamphetamine. See 21
U.S.C. § 841(b)(1)(A)(viii); United States v. Payne, 

, 645 (8th Cir.)
(district court&s determination of drug quantity for sentencing purposes reviewed for
clear error), cert. denied, 

(1997); United States v. Maza, 

,
1400 n.4 (8th Cir. 1996) (statute does not differentiate between d- and l-
methamphetamine), cert. denied, 

(1997).

       Wilson also contends that the government violated Brady v. Maryland, 

(1963), by withholding cooperation agreements with its witnesses, but the record
shows that the government indicated to the district court at sentencing that each witness
was cooperating under plea agreements with the government. See United States v.
Stuart, No. 97-1671, 

, at *2 (8th Cir. July 31, 1998) (to show
violation of Brady, must establish government suppressed evidence favorable to
defense and material to guilt or punishment). Wilson&s additional argument that the
government used “statements of witnesses it did or should have known were
committing perjury” amounts only to conclusory allegations of perjury which are
insufficient to set aside his conviction or sentence.

       Wilson next raises a double jeopardy challenge to the prosecution. Because he
did not raise the issue in the district court, however, he may not raise it for the first time
on appeal. See United States v. Santana, No. 97-3450, 

, at *3 (8th
Cir. July 24, 1998). In any event, “the double jeopardy clause does not bar prosecution
of a defendant for conspiracy when the defendant has previously been convicted of
certain overt acts charged in the conspiracy.” United States v. Thomas, 

,
149 (8th Cir. 1992) (citing United States v. Felix, 

(1992)), cert. denied,

(1993).

      Wilson next argues that he did not receive credit for time served, as required
under 18 U.S.C. § 3585(b), but the district court had no authority to calculate such a
sentence credit at sentencing; such authority rests exclusively with the Attorney

                                             -3-
General and the Bureau of Prisons. See United States v. Wilson, 

, 334-35
(1992). Wilson&s arguments that he should not have received sentence enhancements
for a 1988 burglary conviction, for a managerial role, or for career-offender status fail
because the district court did not enhance his sentence for any of these reasons, and
instead applied the mandatory statutory minimum sentence. Finally, we find that the
ineffective assistance claims he raises would be more appropriately addressed in a 28
U.S.C. § 2255 proceeding where a record can be fully developed. See United States
v. Mitchell, 

, 1193 (8th Cir. 1998).

     Upon review of the record in accordance with Penson v. Ohio, 

, 80
(1988), we find no nonfrivolous issues. Accordingly, the judgment is affirmed.
Wilson&s motion for substitute counsel is denied.

      A true copy.

             Attest:

                     CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT.




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