Craig,
My 255/70x16 tires in the mock-up are 10 1/4 inches wide; on a 7 inch wide wheel with 4 3/8 back space. The back space should have been 4 inches. The 7 inch wheels I have are 8 inches in total width. They are steel wheels. They fit with about 3/8 inch on the bed side and I can run my hand around the fender well on the fender side without binding.
Of course the rubbing will have to do with body roll when you are driving, but the tires should fit without any problems.
