I've got a 5" exhaust, but the frame rails hinder me more so than my exhaust. I was thinking of scabbing 2 pieces of C channel perpendicular to the frame so that the spare sets flat against the C channel and the frame, but I think it would stick down further than I am comfortable with. I may just pick up a good used 285/70/17 as a spare rather than my original plan of buying 5 tires and keeping the spare in the rotation like I would like to do. I don't like the idea of the spare rolling around in the bed all the time.