I spent over an hour trying to find pics with no luck, but a 295/65/15 BFG Drag Radial on a 15x8 wheel with 4.5" backspace physically fit our '64 Savoy with stock location leafs, but it would not have been very driveable. The tire would have rubbed on the inner quarter panel above the wheel lips with any moderate suspension movement. I'll post pics if I run across them.

With that said, I believe the M/T ET Streets do not bulge as much as the BFGs did. (I mocked it up around 10yrs ago...when BFG's were the only ones widely available with that size.)