Would these Mustang 18" rims fit?

Uh yea, they do fit. Post #12 is not CGI. AND spacers are fine if done correctly.

To the OP:
As usual, you got yes and no, LOL. But there's whole big long thread showing cars running them, sooooooooooooo......................

You are running a rim with a bolt pattern in millimeters, not inches. Yes they fit, but they don't fit the hub as Chrysler designed.
Mustang rims and spacers, no thanks. Why not do it the safe,right way ?