bsequent to sustaining a sex offense conviction. U.S.S.G. § 4B1.5(a), 18 U.S.C.A. *859 Philip M. Koppe, Asst. U.S. Any., argued, Kansas City, MO (Bradley J. Schlozman, U.S. Atty., Cynthia L. Phillips, Asst. U.S. Atty., on the brief), for appellant. Stephen C. Moss, Asst. Fed. Public Defender, argued, Kansas City