Help me ID these wheels

I have zero experience with a scamp. (That's Plymouth version of a Dart, right?)
But it looks tighter than a duster/demon. 15x7 probably fits easier/better.
So the answer is.... don't press for the very biggest tire that can possibly fit. Get the best tire for the application (drags, handling, or just cruising) in a size that you KNOW fits.
Yeah it’s the same as a dart. Tighter wheel wells than a duster. I’ve seen others fit a 15x7 4.25 wheel with a 255/60r15 on the same car with the same rear. Only difference is my car has rear disc brakes which adds 1/8th inch of track width to each side