Is it still small bolt pattern factory axles?

If so 4.5" backspacing will work. But you might fit a 245/60/15. But 235/60/15 is more realistic cause the 8" wide rim takes the tire bulged outward. And a 235/60/15 on a 15x7 with 4.25" backspacing is a safer bet.

On my 68 Dart, I have 245/60/15 on 15x7 4.25" backspacing on a factory stock small bolt axle 8.75. It barely rubs on inside and out. Has worn leaf bushings.