Rear wheel/tire math problem, 69 Dart...

69 Dart...

255/60/15 Drag Radials
7" wheel with 4.625 of back space.
Tire has a 10.1" section width.
That results in +/- 1" of sidewall to quarter lip clearance.

So if wheel and tire combo was switched to:
295/55/15 Drag Radials
Tire has a 12.2" section width.
10" wheel with 6.625 back space.
That results in ______" of sidewall to quarter lip clearance.

LOL...three of us come up with different answers depending on the math used.

What says the FABO?

PS: Don't worry about leaf spring or tub clearance; we got that!