You won't necessarily need a computer for the trans. It depends on what trans you use.
OP, Anything in particular you're looking to get out the auto trans? Do you want to keep the overdrive? If you can deal with a 3 speed auto, the TF999 found in late Cjs and early Wranglers will bolt up to the engine (not sure about the transfer case) and doesn't use a computer. And it's a factory trans so should be a fairly straightforward swap. But it is a 3 speed with no o/d.
77 CJ-7- AMC 360, Edelbrock cam, MC2100, Fenderwells, CJ T18/D20, Chevy D44/EB 9" rear, Trutrac f/r, 4.11, SOA, 1.25 lift shackles, 35x12.50 BFG KM2s, Shackle Reversal