Radio Active System Problems Wiring

Hello, everybody.

I was a silent reader so far - I always found enough information about the search to get problems under control.

But now I am faced with a mystery:

My V8 has a Gamma CC radio installed.
(Part)Active system - rear are active and front passive speakers.
Unfortunately, the previous owner has run quite a lot of nonsense in the radio shaft, where the entire line of the speakers was simply cut off, including ISO plugs. I'd like to put all the original cables back on and operate on the gamma.

I have a 90s V8 with climate, telephone preparation, duo sound and GRA.
It also has an amplifier ( 445035225 ) for the front speakers over the glove compartment.
In this constellation I simply find no suitable circuit diagram with active system and standard amplifier for the front speakers.

Maybe one of you was facing the same problem and can help me.

Dear greeting and happy holidays desired
Max