I don't want to re-invent the wheel

If you want them tucked in nicely you need a 15X10 with a 7.5" backspacing. I had 325-50s on the Barracuda, springs moved in, in the stock wheels on a 15X8.5" Centerline with 4-7/8" backspacing but the rims were to narrow and I ended up switching to a 275-60