235/60/15 on front of duster?

There are 4 bolts that hold the k-member in place. I am referring to the front 2. And no, 4.25 is not the standard BBP backspace. OEM Chrysler wheels are always centered. A 15x7 rim would have 3.50" backspace. Add 3/16" for the lip. The original OEM Chyrsler Cordoba steel 15x7 rims that I have don't fit. The backspacing is wrong.