I'm having some trouble replacing the headlight bulb on my 1992 190E. The instruction manual instructs you to turn the plastic collar behind the bulb counterclockwise and pull it out. Well, I tried turning it and it just won't move. I thought that maybe it was stuck, so I tried to remove the other bulb and the collar on that bulb won't move either. OK, so I must be doing something wrong. How do I get the bulb out so I can replace it? Thank you very much for your time.