Th350?

First, you will be hard pressed to find anything but a Chevy th350. They are much more plentiful. That's the one you want anyway. Hot rodding is expensive enough without using uncommon or unpopular components. As far as the tail shaft goes you may just have to measure the length of what you have and then find the th350 that's the same or close. Having a custom length drive shaft made is no big deal. Any machine shop can do that for you.

Ok thank you, I'm having a hard time finding a th350, there's a few Pontiac 350 trannys around, I believe that some of them bolt up to SBC? And some don't? Am I right? And if so how do you know which ones do?

I'm not sure if they do bolt up, but even if it does if its an actual Pontiac th350 you may find its more work to install and possibly parts to modify it will be less plentiful and more expensive. I'm not sure about that though. That's probably why you're finding a few around... nobody really wants them. Having said that Chevy th350s should still be a dime a dozen even though they're not used anymore. Where are you looking? You might also want to think about the 4 speed that was used in place of the 350. It gives you an overdirve gear and will fit anywhere a th350 or th400 fits.

I live in Maine and the 350's ain't easy to find around here, and if someone does have one its been sitting in a she's for 10 years and want 400$ for it. As far as the 4 speeds, I hate them. Always had problems with them. I

There's no reason to have problems with a 4 speed. They're as reliable as the 350. That said, use a 350 or 400 if you're more comfortable with it. Don't worry about whether it works or not. If you're building a performance car you'll want to rebuild it and possibly even upgrade it before you put it in. Don't forget the th350 was used in GM and Chev pickups for years. Check Kijiiji, Craigslist and your local online classifieds. If you can't find a half a dozen th350s in about 15 minutes you're using the wrong search words. And yes, you're going to have to spend three or four hundred for a complete rebuildable core. Welcome to the world of hot rodding. Nothing's free.

Sounds like a good engine swap. Depending on how much HP you`re going to be putting out I`d go with a stock rebuilt Turbo 350 and install a B&M shift improver kit before you install it. My Brother in Law has a 70 Nova with a 350 that puts out nearly 400HP with a stock TH 350, 2500rpm stall converter and shift improver kit set up for street and strip. He`s had that setup for over 10yrs. and hasn`t had a problem with it yet. As for the driveshaft on your G-Body, I think the short tail shaft trans is what you need.