engine swap from 5.0 to 5.8 in a 91 f-150

I just got a nice 5.8 to rebuild for my truck. I have been driving the 302 for over 600,000 miles and just need bigger. I overhauled it once and souped it up some and it was ok but not great for what I do. Big slide in and lots of off roarding. Now I got this 351 and it has all the stuff on it, accesories, brackets, upper and lower intake, injectors and harness. I think the only thing missing is the ac compressor but my old one is the same thing I know. I also know my new exhaust manifolds are a direct fit but I don't think the y pipe is. That sucks because I just replaced the y pipe / converter assembly back in the spring. Oh well. I have a ford motorsport mass air conversion on the truck now for the 302. It converted it to sefi too. Does anyone know if there is a computer available for using that system with a 351? I have a stock computer for a map system 351 in a 91 that I can use but I planned on keeping the mass air if possible.
My trans is a heavy duty c-6 so I don't see any problem there but the flywheel and starter are gonna be diferent or are they? If anyone has any words of wisdom for this conversion please let me know. I consider myself a good mechanic but I have little experience converting stuff like this. I want to get it right the first time.