I saw an 04 GT at a dealership once that had 05 Mustang wheels on it, and they were WAY inset. It looked really stupid. You'd have to get hella wheel spacers to make them even tolerable. The worst part was, the car was a blacked out, black on black GT, that HAD deep dish black Bullitts on it, but the dealership owner 'didn't like that', so he had them swapped off for the 05 wheels that they had in stock, which looked like a 400lb woman wearing high heels that are two sizes too small. Stupid! This was when I was looking for a Mustang before I bought my current one. If it still had those wheels on it, I would have picked it up for sure.