CJ5 V8 NOS 3 speed?

Im serious,

I have a '74 CJ5 which over the years Ive been doing up, (since 1990!) I live in the UK and imported from stay in Virginia back then.

Things have gone a little out of hand as the motor now is sporting forged pistons, polished rods, beautifully ported heads, (Im bragging caus I did them) and well I am expecting between 300 and 350hp, with cams a 650 carb etc.

BUT: here comes the part where I need help from you friendly people in the US, what is my 3 speed manual box going to think of all this? What are my diffs going to make of it (no idea what they are but the rear has a locker - dont know any more then that)

And for final laugh I also have a NOS cheater plate kit for it, this I can jet from around 75hp to 250hp.

Any one know what the transmitions are good for? No one in the UK has any idea. Or thinks im sane either.

thanks in advance.