'92 Sable w/ Premium Audio Preamp

OK guys, I figured it out.

I have been installing radios in cars since they were 8 Tracks.

Just not Fords (I don't like Fords) with this preamp set up.

The trick is to wire all the speaker negatives all to (here the WHITE/ black wire)

the common negative to the preamp.  This is on the output side of the

aftermarket receiver going into the Ford preamp.

The preamp input is five wires- one common negative with the four

positives for the corner speakers.  Works like a charm.  I just had to think of it a

little bit. 

It was Crutchfield that told me to tape off the three remaining speaker

negatives.  That was wrong. This left the speakers essentially out of

the circuit.  I was pressed for time and I tried to take a shortcut by consulting

the Crutchfield "experts".  When I ordered the Blaupunkt I talked to an

expert who assured me that "Premium Audio" on the speakers did not mean

a thing.  Wrong.  Three phone calls later, Crutchifield conceded a preamp

setup.  I'm a law student and my professors do not leave me time to do the

things that I really enjoy - which could include tearing up carpet and body

panels to install upgrades.

 I probably did not need the damn PAC adapter but I am not rewiring anything

again to take it out - no time.

 As the system is configured right now I can pop the OEM radio back in when I

go to sell the vehicle.

So remember, "Premium Audio" on a Ford of this vintage means

PREAMP.

Still have not lost the touch after all these years.

The Blaupunkt fires up great and I have adjusted the audio so that

the sound distorts just under maximum volume (~95%) output.  Otherwise

it is clean sound.  Sure it can be tweaked more but this is perfect

for a 16 year old who got his license three days ago.  If he wants to turn

the car into Carnegie Hall so be it.  Right now I am not worried he is going to

wreck while fiddling around with a portable CD player rigged up through

a cassette adapter device.  Now he just sticks in his CDs, burns or otherwise,

and enjoys the ride. 

Thank you all for your 2 cents worth.

The problem has been resolved.