I just bought a 1995 E300D and have a head unit sitting around with an AUX-IN. I was planning on buying a stereo wiring harness and dropping it in but everyone over at (another popular MB forum I won't name) said that aftermarket units wouldn't play with the audio system? Have you had any problems with this? Thanks for the write up, before I read this I was going to buy the Grom AUX-in adapter instead of swapping in the newer head unit.