Interesting, when I put 245/60-14's in the back of my 72 Swinger, abut 20 years ago, I had to roll the fender lip and still had less room than you do on either side of the tire. In a hard corner my sidewall would just rub the leaf. Never rubbed the outside though. I had maybe 3/4" clearance on both sides of the tire. I cannot imagine being able to fit a tire with a bit more than an inch wider in there.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.