I spent an hour or so doing this today and thought it might be useful to others who want this also for coolboxes or whatever.

As per a previous post i didn't manage to find a permanent live in the boot so ran a wire from the fuse box. You need topop off the fuse box cover and remove all the torx bolts that hold the black plastic fuse box holder in place, the fuse box then unclips from that panel and you can pop the cover off.

I then used a multi meter to find which wires had permanent power, i chose fuse 16 for the magnetic clutch (aircon pump), srtripped a bit of insulation off and soldered my wire on to run to the boot.

This wire i then dropped so it came out near the accelerator pedal, undid the grey plastic pedal stop and slid the wire under the kick panel to the right of the accelerator pedal.

Without removing the plastic sill cover i slid the wire under that all the way to the back of the car, lifted up the boot carpet and ran it into the right hand side storage quarter panel. I was using a Passat boot 12v socket so had drilled a hole (27mm) already, i then soldered the live wire and ran an earth wire to the boot light buttoned it all up and it works a treat.

Enjoy folks