Or you could get an 4.2L F150 v6 engine too from a junkyard or something. If you plan on FI anyways, why not go with a H/C/I swap. I'm getting mine installed right now;
Super Six Motorsports I got the stage2+ because I'm not going to add F/I any time soon if at all. Stage 3 would be your better application. Those #'s posted on his site are at the crank.