Could you please tell me how to measure that 4"? Is it from the inside of the tire to what?
Flop the rim (without tire)so that you are looking at the inside. put a board across the rim from edge to edge and measure how far it is to the surface the bolts come through.
On my '51 3800 the 4" backspacing puts the rim less than 1/4" from a tie rod end.
