Q7 DVD headrest player questions!

[DamoM]

I have bought some replacement headrests with 9" screens which each have built in DVD players with usb and SD card functionality plus various other gizmos for keeping the sprogs amused in my Q7.

My car has factory fit digital TV and I have enabled TV in motion.

I have bought some a/v cables from kufatec to allow the output from each player (each has an aux output) to be played on the main screen in the dash (via the aux in 1 and 2 on MMI) and also another set of cables for the output of the digital TV signal to be available to watch on the screens via their aux input.

I have done the (relatively) easy bit by installing the headrests, running the cables down the inside of the seats and zip tieing all together and putting the seat backs back on (which was thankfully much easier than suggested by most threads on the subject...!)

My questions are as follows:

• Power Source - where should I source the power from given that I want a switched supply, preferably an accessory one, and how should I route said cable? All of the power in the central console (telephone handset and lighters) is permanently live it seems.
  

• Feed to and from digital TV unit - kufatec have supplied rudimentory instructions on which wires attach to which pins in the Tv connector. I am not 100% sure that I even know where the TV module is! I think that it's under the DVD nagigation drive on the right hand side of the boot.
  
• How best do I tap into this loom/connector? I am quite capable of soldering.
  
• How do I route the a/v cables through to the front seats? I can't find any obvious loom conduit.
  

Many thanks for any help!