I have a 1989 w124 I want I already have an aftermarket HU in my car it came with it when I bought it a couple of years ago...
I'm about to install a new one that I bought its the kenwood KDC-X494.

Last time I took out my HU was to connect some RCA's to the rear of the HU and the remote cable for the amp.
Like I said I want to replace the HU just wanted to know if you have a diagram or something that could let me know what each wire is for?
Not the ones on the HU I mean I got a diagram when I bought the HU but the wires in the car what do I connect to what?

if you could help please

-Thanks