8 3/4 Brake drum face to leaf spring measurement needed.

The wheel mounting surface to wheel mounting surface on a SBP 8 3/4 is 57 1/8”. Center to center on the leaf springs is 43”. The leaf springs are 2.5” wide, so, outside to outside on the springs is 45.5”

57.125”- 45.5” is 11.625, divided by two so it should be

5.8125” (5-13/16”) from the WMS to the outside of the spring for an A-body with the stock spring locations and a SBP 8 3/4.

My ‘71 Dart GT has an A-body 8 3/4 with BBP axles (11x2.5” drums) and that measurement is 6” on the “tight” side, which also makes sense given the change in track width from SBP to BBP. The other side is closer to 6 1/8”. Which brings up an important point.

You have to measure YOUR car. Because with body tolerances being what they are anything +/- an 1/8” from 5.8” would be well within spec. And there are cars out there further out of spec than that. Just because my or someone else is else’s car measures something doesn’t necessarily mean yours will.