From my former life working on jeeps I know the nv 4500's are probably a little beefy for a 235. a 4.6 liter stroker pushing about 250/350 would be on the brink of blowing a Ax15 and loooking to swap to a NV 4500. You can probably save yourself some space, weight, and money by looking into a NV3500.
Hell if you going through all that trouble, look into the S10 5 speed, can find them dirt cheap, will handle the power and LOTS of people have them behind GM 6's
