here's my opinion, 350 Chevy small block (built ford tough with chevy stuff) or if you wanna stay ford a 351 out of a bronco. thats if you want to go little, if you wanted to go bigger 383 stroker, 408 stroker, 427 stroker. Anything big like that, that you can get out of a donor vehicle I.E. bronco, and drop the C6 or whatever tranny it has bolted to it in there. keep it naturally aspirated, while its out of the truck do new pistons, forged crank, heads, exhaust manifolds, injection system, or holley 4 barrel if its carbed.
Really if you looking to make it into a sled puller your going to be up there with built twin turboed D-Maxes pushing near 1000hp and 1700+ LB-FT
Sooo my opinion is to go with the old saying "there's no replacement for displacement"
Also do you have a 4.6??? because you talked about doing a 54 swap, anyway those arent too bad I dont think my buddy did one (had one done) on his 97 Expy after he ran the 4.6 a lil too hot... or out of oil

and it threw a rod right out the side of the block

Cost him about 4K to do it, and im pretty sure he used a crate engine 5.4 but I could be wrong
Good LUCK!
Either way its going to be a bad B*tch no matter what you do with it!
