A GM front 60 is 69" WMS-WMS. With a 13" wide tire (MTRs, IROCS, etc.) on an 8" wheel w/ 3.5" of BS, you'd end up @ 83" outside of bulge to outside of bulge. I've seen guys running around with this combo on the street and they run wide flaps. Though this USUALLY works, the law says the tire must be COVERED, not just on the back side.