I am in the middle of installing this HU in my 2003 C320. We have been taking it slow so we don't break anything but here is what I am tell you so far.
If you have the Bose fiber system it is a pain in the butt to get everything installed. I needed an amp (Polk Audio 5 channel), the Pioneer Carpi system to get my steering wheel controllers (you can get the VSS signal without it but the Carpi makes it easier). All of the speakers needed to be replaced (Polk MM6501's sound really good) and all of the interior trim needed to be removed.
Running the wires through the door wasn't that bad a
