Rear power outlet on a 2012 wagon?

[Coldcomfort]

Hi all,

I have just installed a second battery in my truck. Mainly to supply my fridge in the rear. There is a 12v outlet in the rear from the factory. I want to use this and use the existing wires. I have been told that I can intercept these wires behind the passenger kick panel. Has anyone else ever done this? Any info on wire colors etc?

Cheers all.