I run 285/75-16 mud tires without a lift and I have no rubbing issues.
The 6-inch lifts that are available require some cutting of the frame crossmember and put the CV's at a bad angle. If you must lift, go with a more mild 3" OME or something similar.
Visit my clubs forum (
FJ BRUISERS FORUM - Index) for discussions about lifts.
-Rip