Well, Im back in town and Irom helped me dig back into the treg.
Long story short, we had to Vag the codes again, as simply changing to "4" did NOT turn on the "standard" radio outputs, as described earlier, in my case. What DID work, was changing the final code to "7" as well. I'll recap, but Irom, you are the Grand Dragon, so correct me if I've forgotten something:
I started with: 0003077
We changed it to: 0023477
(this took care of a couple other VAG's- nav acceptance, seat belt chime, leveling, see FAQ for details). We were hoping the 4 in the fifth place turned on the "standard" 4 chanel output as illustrated by Spock above.
It did not- (and we didn't have a test speaker hooked up to verify).
Irom deduced we needed to change the last digit like this: (based on his experience of switching from stock to Nav, his numbers
I changed the last two numbers to 07, like mine is setup, this turned off the oem amp, turning off the front speakers, but turned on "extra" 4-chanel speaker output.
I then changed the last two numbers to 17, this turned the oem amp back on and left speaker output turned on, but did not add any region code.
So ultimately this worked: 0023417
Nothing else changed- still had no seat belt chimes, no nav acceptance screen, and the new chanels were putting out signal. good.
Anyway, the output is finally on, and I'm looking into amplfying and replacing stock speakers.
One Last Important note: Before Rom vagged the new outputs, I made a temporary fix to improve the front speaker bias on the premium stereo: I hooked up a very cheap spare amp I had laying around the house- I simply tapped into the bass speakers in the rear doors (wires near cd changer, see wiring diagram). Wanted people to know this revolutionized the stereo. I KNEW something was missing/wrong in the "Premium" system, and this confirms it. Even slight amplification brings the rear speakers to life. It is a must do for anyone wanting to improve the sound.
I'll post pics when the "big" install is done. Thanks again for the help. Hope this is useful for others.