I am planning to get KMC XD Rockstar's in either 20", 22", or 24"..

My truck has the 6" Fabtech Lift, and soon to have a PA 3" Body Lift, I want to run a 35", 37" or 39" tire with the rims, what combination will work best?

Any help would be greatly appreciated. The truck is 1998 Ford F-150 4x4 Fleetside, Extended Cab.

 

Personally, I'd go with a 37 inch tire on a 20 inch wheel.