Thanks for the help. I'll spend some time going through the codes.
I had a feeling it was aftermarket, but the quality is top notch. So far every part related to the changes has the MB stamp on it, and the service records don't show any body shop work.
I've not found any signs of modification or damage, so I'm not sure.
The story behind the purchase is a long and interesting one. Unfortunately I can not ask the previous owner about the car. He passed away more than two years ago, but according to the family, the car was his pride and joy!