Eary VS. Late A-body rear end widths

convx4 said
So the 66-72 small bolt 8 3/4 has a width of 57 1/8"
The same housing with big bolt pattern axles has a width of 57 13/16"
Now the 73 and up big bolt 8.25/7.25 axle has a 56 3/4” width.
So the difference between big bolt pattern 8 3/4's is 1 1/16"

From my measurements the 8.25/7.25 width is as narrow a 8 3/4 can be made with out any other modifications allowing a 15x7 wheel to fit a dart swinger/scamp.

Why are people narrowing housings and not getting the maximum benefit from their effort?

I fit a 17"x9" into mine. No modifications, stock 8 3/4 sbp axle, stock spring location, stock wheel well. The fit was made through proper backspacing and offset on a custom rim. I have a 1/4" on spring side and 1/4" on fender side. I think the tire is just under 11" wide. I don't have a straight on rear photo, this photo makes it look a bit pushed out but its just the angle. They are tucked in there very nice, with a great stance. The fronts are 17x8. All stock there too, Kelsey Hayes setup. PM me if you want more details.