Aftermarket CD install in 1991 300D

:( I removed the OEM (Becker) radio. I cannot locate the amplifier, wiring harness, and antenna cable. I have an Alldata wiring diagram, but no clue as to where things are. Any help would be appreciated. Thanks

I found it in the right side trunk panel. Looks like I will have to run the antenna coax and speaker wires from the trunk to the dash in order to install a Pioneer CD player. Does anyone know if the antenna coax will reach the dash or is an extension going to be necessary?