I ran into a similar problem with my 29. I'm running 185/65 X 15" in front and 10.50 X 31 X 15 out back. I wanted the wheel to look the same as far as offset goes front to rear. I contacted The Weel Smith in Calif. and he made me a pair of 15 X 8 steel wheels with a 6 1/8 back spacing. He said that was the limit for a 8 inch wide wheel. they are perfect. My point is if you give them the backspace measurement they will build the wheel you need.