Why not a 13B-REW? or better yet, a bridgported 13B with carbs? Or the Renesis RX-8 engine?
RB26 and 2JZ will destroy the body I think, and it won't be fun anymore :(. Besides, it's worth doing something original, don't you think? Oh! Maybe you can fit RX7 suspension parts, and brakes to this car. Just an idea.