^^^^^ all good advice (er, except for the previous post). I built, and still own, both a SBC 4 speed 86 and a Northstar 5 speed 88 with IMSA body kit, vett rotors, custom dash, etc. both fun. I obviously have much more $ in the 88, but I personally enjoy the SBC 86 the most. nothing like brute american muscle (IMHO. and it's just that).
TH trans isn't up to the task for most drivers. the Getrag 5 speed is nice, but getting harder to find a good
one. The 4 speed from a v-6
Fiero (stronger case that the 84 4 banger) is my preference. 4th is an OD in the 4 speed, and I've found them to be very strong.
or you could just buy one of mine, as they sit in the garage mostly, since I discovered street rods.