overdrive trans swap options for sbc??

[KLAB]

I'm thinking about what our options are for my step dads 68 vette. Here are some details:

'70 LT-1 block
GM '70 LT-1 cam
LT-1 domed pistons
camel hump heads
Muncie M21 4 speed
factory 3.73 rear

He has another factory rear with 4.11's he is thinking of selling. I suggested we swap in the 4.11's, and swap in a t5 or t56. That would be badass, but we would have to swap in a used trans. can a turd gen T5 tranny bolt up to an sbc, or even an LT1 T56? I assume the T56 would be harder with the lack of computer, but also wondering is the T5's were fully manual no electronics? and no were not swapping an LTx or LSx. I'd do what I usually do and get deep in the research but I'm back in school and seeing if anyone of yall have some info.