I know it would cost a good bit more, but weld was willing to work with me to fit 18s made for the gt500 on the SHO. Might be worth looking at, but much more $$ than steelies. Otherwise, if steelies are on your horizon, look for 18s of the SEL/SE models, and see if you can test fit on, you can get 18s or 19s that will be a bit lighter than PI steelies.