rear brake swap question

Here is the housing end dimentions to some popular rears (and some not so popular ones too!) I thought the 8.25 was on this as well but I was mistaken.

I have read that the 8.25 backing plates have the same pattern with the exception of the bottom bolt hole that can be drilled out. What I dont know is if 8.25 complete brakes will work on an 8.75 because I dont know the measurments of how far the axle face is from the housing ends bolting surface (does that make sense? lol)

Oh! The housing ends on my now trashed 7.25 (1976) was the identical pattern as the 8.75. The brakes were 9" and I should have for curiosity sakes made some measurments.... oh well it's gone

Though I have not checked, I do beleive the 9.25 (1974) also has the same housing ends as the 8.75

What was the question again?

Axle Housing Ends 2.jpg