Ok, so dad bought himself an '88 F250 460 EFI w/C6 trans, heavy duty axles, and only 62,000 original miles. Truck was sitting for 15 years, and he paid $650 for it. Besides one dent in the bed floor, the truck is perfect. Being a 460, it's getting about 8 MPG (bone stock). I know there isn't much more you can get out of it, but he wants to give it all its got. He has already decided to use a true-dual setup with 2 FlowMaster Super 44's Being 16, I don't have much experience as to building engines, however I can rebuild them STOCK, which is why I could use some insight. He and I want to know the best options for a Camshaft and Intake to increase HP and MPG (and if changing EFI to carb is a good idea) Also looking into putting an AOD Trans in there and lowering the rear gears, of course. The truck runs like as if it were new, so no issues there. Any help would be appreciated!!