SBP Steel wheels: How to tell if 5.5 or 6.5?

Greg the bbp has a 6" wheel-- but not the sbp, that 6" wheel is also uncommon-- read on here some time ago what vehicles came with it but cannot recall now.

If you have the 5.5" 14" wheels-- then your set for sbp.

here is a visual, basically the rim face sits farther down with the 5.5" wheel, the wheel with the tire is 4.5"