Hey, thought I'd bump this up as I'm having a similar issue... My '68 400 had 215/70R14s on all around with 14x6 Rally II. I changed out to 215/65R15 which are the same diameter, on American Racing Outlaw I wheels... unfortunately, the Outlaws only have 3.5" backspacing, where the 14x6 Rally II are 4" backspacing...
and only the right side rubbed at the very bottom of the rear of the front wheel well. left side was fine...
now about 30 or so years ago, my bird had been hit in the front, and there is a frame patch, but it was checked and deemed okay...
anyway, I have a set of 15x7 Rally IIs which look to have 4.25" backspacing. I'm gonna have one tire mounted up to see if it will be enough to clear....
Should also note that I believe the springs to be original to the car, and each front spring has a twist block spacer installed.
