What custom backspace would you order?

FWIW, I am pretty sure my police wheels have a 4 1/4" backspace. they are 7"wide. based off that I am thinking 4 3/4 backspace.

Even if your rear isn't in you could probably measure from the leaf spring perch to the mounting flange and get an idea of what room you have there.

Honestly I would probably go with a bit more spacing if anything. You can make up the room with a spacer then if you had to. You can't the other way around. I also personally wouldn't run more than a 1/2" spacer if I was to run one.

hope this helps :dontknow: