Ford actually has used 3 different 8 lug patterns, so thy are a crapshoot for fit. Most steel aftermarket 8x6.5 patern will fit with the stock lugnuts and clear the axlestubs. I have run a 15x8" with 0 offset and 35's on a 79 RC with 5" lift with issues.It had Dana 60's Front and Rear FF from a 1 ton single wheel.There caliper and drums had to be milled slightly for wheel clearance.The 35's were not always avable in 16's back then.