which head for the 4.6L?

[Hammer]

I think your numbers may be rated a bit on the low for both heads, I gained 130rwhp with the FRPP heads+intake and a set of regrind cams and have seen PI swapped cars in the 280rwhp range. IMO a headswap is a must on any pre '99 car.

I'm quoting numbers on a BONE stock 96-98 car without reground cams using "out of the box" FRPP pieces. The old yellowjacket gained about 65 rwhp with the FRPP head\intake alone, but had a lot of bolt ons to begin with, so its hard to estimate what a "stocker" would do. Ford motorsports quotes a gain of 35 hp with the heads alone. (which I also think is conservative)

I also don't like to estimate high and then see someone disappointed when they get it on the dyno...