275/60/15's on 15x7 cop wheels on a 71 Dart?

For 67 and up Darts...255/60R15 on a 7" rim with 4 1/4" back space will fit with no rubbing...stock rear suspension and no rolling of fender lip. Not a whole lot of room on either side of the tire though. I have seen that setup in person and will be running that on my Dart in the next month or two.

I highly doubt that 275's will fit.