I have since decided that I will go Dana 60 for a few reasons, strength and availability mainly. Probably going to try to throw a Dana 70 in the rear as well but probably after the 8.8 grenades. All good information on here so far. Be ready to spend some cash, especially if you get a shop to do the work. If doing it yourself, have cash and another daily driver available for a while. I won't be doing the solid axle until I have another vehicle besides the ST and '69 Cougar and add the ST to the garage of "fun vehicles."
Since there's only one person that I know of that has done a Sport Trac, Chad will have the most useful knowledge. You'll also want to spend a lot of time on the other ST forum and a lot of reading on pirate4x4 (just check your feelings at the door and maybe not mention doing this to a Sport Trac, lol).