1993audi90

I've gone through 8 pages of radio threads and didn't see the answer I am looking for.
I have a 1993 audi that came from the factory with the Delta unit. I had a 1995 90 parts car that came from the factory with a Gamma unit. The 1995 front speakers and 1993 front speakers appear to be the same. The rear door Gamma speakers are amped. The 1993 rear door speakers were missing. Tweeters are there. I can pull the amped door speakers and tweeters and install in the door.

I saw this posted at some point:

Should be on the black connector
Red/blue = +12V DC Battery (constant)
Red = Switched 12V
Brown = Ground
White = Remote for antenna/amps
Grey/blue = Dimmer

On the brown connector - forget which is L/R though
Black/green = Left front +
Black/white = Left front -
Black/green = Right front +
Black/white = Right front -

On the red connector - These should be connected to RCA plugs and plugged into a rear pre-amp out
Blue/green = Left rear +
Brown/red = Left rear -
Red/green = Right rear +
Brown/black = Right rear -

I connected the gamma radio in the 93 dash and believe it or not it works. Sort of. All power and lighting functions appear to work fine, front speakers work. But, no rears.
Anyone have any wiring diagrams of non-amped speakers vs. amped?