Noobie Bronco Tech Questions. Flame free zone!
Dude, you are making this sooooooooooo much more complicated than it needs to be.
You are not going to notice a gain or loss of 5hp/5ftlb in a 5,000lb truck.
You want gains? Concentrate on the heads and/or displacement, just make sure the exhaust is large enough to support the volume the heads...