I thought about putting AMG badges on my Crossfire SRT but decided against it. Instead I installed Supercharged badges on my fenders and a SRT6 badge on the right lower corner of the glove box.
The crossfire was a joint venture by Daharmler Chrysler not Mercedes Benz.
You own an American car with German engineering not an SLK 32. Be proud of the fact that your car is unique and will become a cult classic in years to come.