Does anyone know what the original size/fitment/offset specifications are for the 2008 Mercedes-Benz CLS550 (not an AMG model/option).

I am wanting to purchase/replace the OE wheels on my wife's 2008 CLS550 with something like the newer (2010-2011) AMG style wheels and will likely purchase on-line, i.e. either "takeoffs" from a private seller or used wheel/tire dealer or new from a wheel supplier. Want to ensure I am ordering/purchasing the correct wheels that will fit properly and not require the use of spacers, etc.

I do not plan to change the wheel diameter and will stay with the OE wheel size/spec. Thats the way MB engineered the car and I want to avoid problems (love the look of the 20"s, etc but its not for us).

Would appreciate info/advice from any other CLS550 owners or otherwise Subject-Matter-Expert(s)