Wheel and Tire Help... 65 Barracuda

4.125" backspacing is probably going to put tire closer to the fender lip than the spring on the back. I use to run the centerline small bolt pattern wheels 15X7" with 4-7/8" backspacing and those were close to the spring I would run a 1/4" spacer with a 245/60/15 tire.

I think that backspacing will probably work on the back without spacers. Not sure about the front I always ran skinny wheels. Good luck!

Here is the Barracuda I ran them on it's pretty tight. 4.5" BS would have been my prefered backspacing on the 7" wheel.