I always thought that 225 would be too wide for the front? I'd also need to get wheel spacers for the back, didn't know it would be capable of fitting that wide a tire
The factory backspace on a 15x7 rallye/cop rim is 4.25. When you run 7" wide rim with 5.72 backspace you are pulling the tires in an 1.5" inches. That give you room between the fender lips for more tire. But you have to keep the diameter down.
I've run 15x7 4.25 bksp cop rims with 225/60/15 on my 68 Dart. And 15x8 4.5 bksp rallyes with 245/50/15's. You just gotta really watch the lower front fender lip to tire clearance.
The rear of the 67-69 Dart have that fender skirt design that hurts clearance. And the 70-72 have it too. A buddy of mine had a 71 Swinger that had to lip the rear fender to fit 245/50/15 road race DOT tires with 15x7 4.25 cop rims. Those tires are a little wider then regular street tires.