since its such a popular thread I figured I would mention that while I was browsing ebay I saw many gm stereos that had the right buttons to clear codes thru the radio instead of trying to press the gas pedal or those weird tricks, many were as low as $10. im not sure if the proper connections are in base cars to put in a more advanced stereo, so you might want to check with the dealership if you can remove the "worst" stereo option and upgrade to the "best" option and still have all the proper connections and functions.