Greetings,
Thanks to all the previous posts, I'm making good progress on installing a new Blaupunkt Munchen in my 300E. Unfortunately I'm unable to find the fader connections to the rear speakers. It looks like I'd have to disassemble the center console much further to get to them. Question I have is do only the positives to the speakers run to the fader? I've identified the following wires:

right and left out from becker to fader (grey with red and green)
right and left from fader to front speakers (black with red and green)
illumination wire (blue)
ground wire (brown)
This leaves two other wires (with red and green stripes) that must be output to rears.

I did find the connections near the radio that join the speaker wires to the fader front output wires.

My question is, to bypass the fader, can I simply splice the right and left from the becker to the two output to the rears? (I.e. bypass the fader for the positive wires.) What about the negatives? There's only one leading from the fader. What if I leave the fader in place and use the original output from the becker for the rears and the unspliced front speakers for the fronts?

I've tried searching archives and am still a little confused. Any help is appreciated.