I was curious after reading the other post about which cd players to add in to their w126. I've had this problem since day one, but it never bothered me. I was wondering if anyone else has installed a aftermarket cd player in a 350SDL. I cold wired the cd player and had signals from both front and rear speakers, but could never get the side door speakers to sound. Anyone have any advice which wire operates the door speakers? Somehow I was able to wire the aftermarket headunit without having to bypass the factory amps (behind the rear seat) and factory speaker fader. Any clues? Thanks for the replies in advance!