T-56 In my 84

[SixthFloorFreak]

my dad has offered to buy/build a motor and transmission for me. we initially had talked about putting a Muncie in my truck, but i offered up the idea of the T-56 since we've had trouble finding a good Muncie, and i sure would like them two extra gears. i haven't done much looking around yet, but what kind of price can i expect on a used T-56 out of an F-Body ( i assume that's where most people get em)?

are there any tips ya'll can provide when shopping for one of these trannies?