what ever you put in there make a it ford , we all know chevy wont last long if your abusing it. i would put a 5.0 out of mustang with the multiport fuel injection instead of TBI [all that is a glorified carb] plus the 5.0 would fit better and has the distributor in front so you wont have firewall/distributor clearance issues. and you know that the 5.0 has a lot of more afthermarket support than the tbi and vortec
plus you could bolt on the np435 . the reason i woulnt put a 351w is that it never came with car type fuel injection only the truck type and its to tall to clearence the hood