So my M3 has the optional Harman/Kardon Hi-Fi system, and I currently don't have a radio since I'm wanting to replace the disgusting aftermarket one that was in there with an OEM one. The thing is, I don't know if mine having the HK system changes what head unit I had or not. I've tried googling and researching and nothing has came up really.

As far as I know, above is what all E36s came equipped with. Of course, I've only even been in one other E36 that doesn't have the HK system so I don't exactly have a strong pool of information to pull from. I know there's a common upgrade to a BMW Business system out of an E46 or something, but I already have a 6-disc changer in the trunk and kinda want the tape deck for a adapter for my phone.

It's a stretch, but does anyone know if what's above it what I need? Or is it some ridiculous, hard to find head unit?