Alternator and Ignition help needed.

If the Procomp box is HEI (like GM, Pertronix, ...), I would gap the plugs 55 mil. If it is like the Mopar ECU, I would gap them 40 mil. You will know the gap is too large if the engine starts missing at low speed and wide-open throttle, since that gives max cyl pressure which is the hardest place to jump a spark (sparks easily jump many feet in a vacuum chamber). As example, my 1996 2.4L Mopar started missing bad when accelerating hard on an interstate on ramp. I lowered the gap from 60 to 55 mil and no more mis-fire. That was from a TSB for the turbo version of that engine. With boost, cyl pressures increase so requires an even smaller gap (or ignition w/ more kick).