All these junkyard build warriors. Don't get an iron block, it's very unlikely you'll make enough power to break an aluminum block.
Aluminum 4.8 or 5.3, put a carb on it, and spray a 150 shot. Focus on the trans and rear end, and other suspension stuff.. get a good platform before you make good power... lighten it up a lot.. Then when the time comes, throw a turbo 408 or something cool in it and have a great set up.
Sunoco hood, ss spoiler, and some weld alumastars. Do it.