I did trade in my 2003 SCrew. I ran 315/70R17 BFG's on my truck with with a 3" body lift and then swapped them out after 60,000+ miles for a set of Mickey Thompson MTZ's which were the same size. The key to this setup was running them on my stock rims. I also cranked the torsion bars enough to level out the truck. There was slight rubbing at full lock, but it didn't hurt the truck or tires as it rubbed on the frame.
I have a ton of pictures over at my old stomping grounds @
http://fordtruckworld.tenmagazines.c...ry.asp?id=1881