OK - deep breath. V8 Explorer 4X4s (and Sport Tracs) need a neutral micro switch installed in the shifter (or wire up a manual switch) in addition to the neutral tow light for the 6 speed models - 07-10. And progamming the 4X4 module is required. Now the Ford programmer is called 'IGS' instead of NGS, procedure is the same.
The kits are still available, but dealerships don't stock them - they have to order them from the supplier and this takes a few weeks. They cost about 250 bucks, but include all the instructions and the warning decals. I bought mine from a dealership in Las Vegas - Gaudin Ford. They sent me the wrong one to begin with, took it back and got me the right one.