Proper backspacing for A Body 8 3/4

These are 15 x 8.5 with 4.25 backspace 275/60/15 on my 69. I have had these wheels for over 27 years and it was not it in budget to change them for the restoration.

4.5 or even 4.75 backspace would be better and I believe there would be no clearance issue with the stock spring location. As mine is it has extended shakles to keep the quarter off the tires. I am ok with that and it gives it the early 80's look I like "at the moment".

In the future I plan on steelies that are 8" with 4.5 BS.