I have a 2015 Equinox (it's a base version) and want to put a rear facing cam in the rear. Does anyone know of a key-switch-on 12v source in the very rear of the vehicle, that I could splice into, to provide power to the cam I'm wanting to get? Hate to go running a lead from the front to the back like in my old stereo install days (leg and back won't take it too well).
Thanks.

[planning on running power to a 'lighter plug' to 5v USB plug, then plugging the cam into that]