Biggest tire on Stock 67-69 Dart

MtNemoMopar said
Do your homework, measure carefully, and get custom backspacing, and 275-60/15's on 7 inch rims is easy. NO other mods are needed.

I see what you're saying, but custom BS is out of the question. I'm on a budget and have already decided to go with the wheels I've already got- 15 x 7 steelies.