68 barracuda tire size question

Yes, they will fit.
I'm running 235/60-14s on 7 inch rims, on the front of my lowered 68S. These are about 25.1 diameter. Your tires compute to 26.4 diameter.Thats 1.3 difference on the D but only half that to the fenders. At stock ride height and on factory rims, it should be no problem. I have lots of room, and they never rub, even under extreme cornering. And I have run taller tires also with no issues.

What the backspacing and offset on your 14x7 rims?

What' the backspacing and offset of factory 14x5.5 rims?