In regards to the Street Class rules, it states that you must use wheels that are +/- 1 in diameter, same width, and within 0.25" offset of standard. However, are you allowed to use wheels that came OEM on a different trim? For example, since I have an iSport, would i have to stay with the stock 16"x6.5", or can I move to the 18"x7" used on the S trim levels? I've also heard that you can use OEM wheels if they can be ordered as a factory option, which in this case would include the aforementioned sGT wheels, and also the OEM Rays wheels. Can anyone confirm that this is true?