I was also wondering if anyone had done this fitment test. Not sure which wheels you are referring to? The 19" split spoke from 2010 are beautiful, but they're forged and about $1200 a piece from Ford. I'm looking at that style, but 18" as I like the more classic look of having a little bit more tire and don't plan to lower the car. My understanding is that the lugs have a different thread pitch this year, so depending on the wheel you may not be able to reuse your stock lugs. While not certain, I can't see that being the case with an OEM sourced wheel though.
Sorry... Lots of rambling and no information. Does anyone have info regarding GT500 wheels on the S550? :shrug: