A body non 7.25 rear end

Our car is an early A ('66 Cuda) and it's running 235/65/15's on "7 wheels.
I doubt it has an extra 9/16's per side as the tires rubbed all the high spots off the undercoating on the outside of both wheel tubs as it is.

Hummm, this concerns me. I was planning to step up to 235s on my '65. Are the tires rubbing the inside of the fender? Is the 8.25" rear end a bit wider than a 7.25"/8.75"?

TIA