Found some cheap factory 8 lug steel wheels off of a 78 F250. I am just wondering if the center holes of the wheel will fit over the front a rear hubs of 81 J20 axles. I didnt have time to measure them and its a long drive if they will not fit. Also, would anyone have an idea of common backspacing for this year and wheel?

I have j20 axles and got some dodge ram rims that have the right bolt pattern. They do not fit.

You will need something with about a 4.125 backspacing I think.

But I have 4 disc and a high steer. But I need the 4.125 to fit..........