Oh man, alot to consider. I appreciate the advice from everyone. My main reason for wanting a Toploader is they are nearly indestructable. My car isn't overpowered by any means at this point but later down the road I'd like to be pushing 400-450 HP. I've thought about the T5 but have heard alot about how comparitively weak they are. Sounds like if I go for the best of of the best T5 450 HP and about 330 lb-ft will be it's ultimate limit.
Overdrive is a nice option though, I know how annoying driving a C4 at highway speeds can be and with the Toploader it wouldn't be any better, although swapping my rear gears could help that.
One question about a T5 install though. Will the shifter from the T5 align with the shifter hole in the transmission tunnel on my 67? Or will I have to cut another hole?
That does sounds like a good deal rbohm, do you know the ID tag on it? I'll have to give it some more thought. I was figuring the decision would be easier than this, haha.