Solved! Gilly pointed me to the exact spot where they fiber cable was: tucked under the taillight. I feel stupid but happy.
I have searched all of the posts in mercedesshop and am still stuck. Hopefully, one of you can help me. I have also posted this issue in the Audio sub-forum but haven't yet resolved anything.
I am trying to install an MC3198 CD changer in my 1999 SL500. Everyone says this should be a no-brainer as the 1999 is fiber and I have the right fiber changer. I have literally ripped my trunk apart and cannot find the fiber CD connector. I have found four connectors bundled together. One looks like a coax for the phone, one is the power plug for the changer, one is a 15 pin female connector sort of like a computer monitor plug, and the last is a 25 pin female connector that looks something like a serial printer cable connector.
Does anybody know what these are and if one of them is supposed to go to the CD changer or is there a missing link that plugs into one of these connectors and has the fiber plug on the other end. I know this sounds crazy but I'm hoping someone has either been through this before or knows the connectors somehow. Thanks.