Stock '05 Bullitt Center Cap size vs '04 Bullitts

Is there any difference? I've tried our stock bullitt center caps from our '05 on our new wheels. The manufacturer claims stock ones fit, but they aren't tight enough. they seem a few mm smaller than the hole. does anyone know if the OEM center caps from 03-04 are a few mm larger? maybe this is what the wheel manufacturer is referring to. I don't want to spend almost $100 on center caps if they don't fit.

Well, I answered my own question there. After looking at a few pictures, I see the center caps are completely different. The 2005 ones have a trim ring, and earlier ones are flush, and appear to be larger. I measured the opening on my wheels, and came up with about 2 5/8, it was dark. that's quite a difference than 2.5" that most people are selling theirs as. just want to make sure it'll fit. I know someone on here has to have aftermarket 18's.