If you don't have too many and they haven't set too long, you might want to try "paint-less" ding removal. The local dealer has someone on the lot every Saturday morning removing (or rather, coaxing) the dings out of doors and fenders. Last Fall I had one removed from the rear door of my wife's 190E. The ding was then about two weeks old and when the guy was through, you'd never have know the door had been hit or worked on. Made me a believer.
1989 190E 2.6