transmission ?'s

Ok I just picked up an 86 shortbed with 172,000 miles and a 4 speed tranny.

i am going to be redoing the motor after summer time, and also want to upgrade the transmission to a 5 speed.

if I go looking for a tranny what years will work?Also is there any good sites on these trucks and motor buuilding for them?

thanksRicky

Oh yea i will be putting up pics of the yota soon.