switched 12 volt supply in boot

[capt kirk]

Hi people
I was looking at fitting a dashcam in the rear window to cover my rear end.
Has anyone found a switched feed to the rear of the van from the ignition switch. I was wondering if the ventilation system in the rear side panel has a switched feed i could get into. I understand canbus may be an issue but i know you bunch are clever and will have thought of that. i know i could use the leisure battery feeds but would like to go the switched version if possible. I have a dashcam at the front and could run a second cam from that but dont really want to run a cable from the front to the back. Sorry if this has been responded to before but i have looked in most of the forum and checked the document store for answers but none were forthcoming.
Thanks guys in anticipation.
Kirk out.