First thing would be to get rid of the speed density and go to mass air sensor, you'll need a 87,88,89 computer (5 speed or auto?) plus the mass air sensor, Ford or aftermarket and the adapter plug for the harness. next a cold air intake, getting rid of the silencer and airbox. After that it's how much money do you want to spend!! Just to ask, what gear set are you putting in?
I want to put a 3.73 gear in it. It has a limite slip, and I believe the stock gear,2.75. It lugs around @ 1800 rpm @ 65 mph. It sucks out of the hole. I have a set of ported and polished, 1966 289 heads with big chevy valves, I traded for a C-4 tranny. They are O-ringed, comp springs, screw in studs, the works. I just don't know what rockers and pushrods to use. I am a technician for a GM dealership,but I like and have owned many Fords. Built a lot of early small blocks,but this is my first venture into Fuel Injection.
I had 3.55's in mine, good out of the hole and you don't get killed on the highway by turning RPM's You might try FPS for an answer about you pushrod's (714)773-9027 They specialize in Ford Hipo mods to cylinder heads and blocks.