I think the rear shock changed sometime in '00. I'm not totally sure. The '99-'00 model years are where all the recalls come from. Those were the bad years. Sometime in '00 they redesigned the shock. the recalls stemmed from shocks actually breaking, but the shock actually had other longevity problems beyond that. If you do end up with a '00 just see if it was in the recall, and really no matter what just get a newer shock off Ebay, or pick up a Works, or some other after market shock.
I have no idea of what a Bellcrank is but if you want to lower the bike I would suggest a complete after market shock.
And hey, check these guys out,
http://www.nrhsperformance.com/, they seem to have a real passion for buell's.