Wheel backspacing for a W200 on 35's?

Its tire time for my 73 W200. The truck has a 4" lift and ancient 35x12.5/16.5 BFG AT's that are in bad shape. For the new tires I'm going to switch to either a 16 or 17" rim so I have more tire options. The 16.5 seem to be getting harder and harder to find.

Does anyone have a recommendation for backspacing on a 10" wide rim with 35" tires on one of these trucks?

Thanks,
-Jon

I'd say 4-4.5" BS should be good. Check what you have on it now?

Depending on wheels some only come in a 9" width also