I run Dr. Diff's offset kit on my Duster and a MT 28x10.50 slick is not an issue nor is a 275/65 MT Drag Radial on a 10" rim. I am pretty sure my offset is 3.75" on both sets of wheels. I run a Weld Wheel with the slicks and a Torque Thrust on the radials. I'm not sure if the later model Dusters have a little more space in the wheel well from the early years, as mine is a '75. I did have to shim the hanger to center the tire in the wheel well (front to back).