The GT40P heads have 4 vertical bars and "GTP" cast into the corner head flange - don't overlook those either. MY bone stock 88GT made 200HP, made 219 with a ported lower, and after going GT40P heads and intake I'm at 60HP (with stock cam) gain over the stock numbers without any tune (tune in progress). A good cam selection would add significant HP to that.
If you need to stay emissions, look for a 96-early 97 Explorer intake with the internal EGR passages like your stock intake. The TB face on the upper will have a rectangular whole for the emmissions, so you can check by popping off the TB. Take the 65mm TB also - requires some minor work to convert, but it's worth it.