Keep it. I agree about selling stuff to people you know and see all the time. Also, I do not think there is any comparison between an S-class and a C-class. The C-class may be newer, but it just won't come close to the beauty and elegance of the w126. If you have just gotten a paint job, which I am sure you spend a lot on, I would keep it for a while.
Tim

PS: I like the Euro lights!!!