Guys,
I am pretty sure the 10.5" rims will fit this project of mine given they have the right backspacing of course, Factory Five updated their frame (MKIII's) to be able to fit 315s on a 10.5" rim:

here's an image of a MKIII Cobra Roadster Replica using Bullitts.
so, anyways, what is the backspacing on the Black FR500s that you sell?
Thanks