Purchased a 91 300E with a BE1432 head unit and wanting to install an Alpine CD changer in the trunk non FM modulated.

I have the cables from PIE, however, To my dismay, there is no factory harness in the trunk from the headunit and MB wants an arm and leg to purchase it. I have the ability to manufacture custom cables, however, gotta have a wiring diagram for this task. (I can make any cable).

Does anybody have a wiring diagram for the MB Factory CD Interface cable?