Hi i have a 2006 f250 with 2.5" lift front and back and i have 315x70x17 BFG on it know and i want to put on a set of 20"x8.5 black rockstars with a set of 35x12.50x20 procomp at's tires and i dont want them to stick way out of my fender i want them tucked in so what size offset backspacing do i need. Thanks

 

I would ask the company or store that sell the RIMS or TIRES cause they would know better than anybody