as far as i know...
k10
10 bolts fornt and rear or some had d44 and 12 bolt rears
v6, 305 v8, 350 v8, 6.2 diesel
sm465, th350, other stuff
k20
10 bolt or d44 fornt. 14b ff rear
prolly 3.73 or 4.10 gears
350 v8, 454 v8, 6.2 diesel
sm465, th400
that's the stuff i'm pretty sure of.