You have the truck, clip & tapemeasure, so measure it up for yourself. Make sure the A-arms are level (loaded) as this will have a slight effect on width, also what will matter is if you intend to have the top of the tire higher than the bottom of the fender opening. The more overlap you have, the narrower the tires will need to be for turning ability. My guess would be that for every inch of overlap, you will probably need about an inch of clearance between the outside of the tire and the inside of the fender, but this can depend on tire profile and total turning radius.
One idea would be to take the front sheetmetal and set it over the top of you clip with tires on and A-arms in full up position, then turn tires back and forth to see at what point you will have interference.
