X-Peri-MENTAL

Please could anybody assist me with a wiring diagram for the W205 audio system with Burmester or at least identify the wire colours? I am looking to fit an active-subwoofer in the boot and need to tap-off the left and right speakers, I had initially thought the job would be easy as I believe the audio system amplifier was situated next to the rear fuse box but I could not determine which wire was which. If this is in fact the amplifier then it should be easy to tap-off from there and get access to +V(Bat) and +V(Acc) from the adjacent fuse box.

Thank you in advance for any information.

Regards,

Kevin.