Premium OEM CD in Premium Stereo Fox

I had this in the sound shop, but it does not get much trafic...

I know that I could get a better CD head unit than factory, but I wanted the 7up car to look stock... That said, the electric side of things was a breeze (plug and play). The downside is I cannot figure out how to wire the speakers. My 1990 has 5 wires going to the amp from the head unit out of the long black eight pins in a row plug on the car harness. The 1996 CD head unit (F4TF-18C815-AC) uses the more squarish plug that is two rows of four.

Both the factory unit that came in the car and the CD unit are premium (need an amp). Anybody have any ideas.

OK more info... the newer cd head unit has a line level out for four speakers +&- to the amp, which is 8 wires. The amp in the 1990 car has five wires, a common ground and 4 other wires for the individual channels. Can I connect one or all of the grounds from the head unit to the one ground input on the amp?

Since it is line level, what harm can be done with experimenting with various wire configurations?

Saleen0679 thanks so much... I have been looking for that for weeks.

Now that I know what wires are what, I am still faced with the issue that the 1993 CD head unit has a ground output for each speaker (4 of them) and the amp in the 1990 car only has one ground as an input. Anyone have comments or ideas?

Seems that the best solution is to get a newer amp that matchs the radio output. I may just put the original cassette back in and be done with it...