I'm not talking about tapping the trailer harness, in that electrical center is the trailer brake controller harness as well as dedicated upfitter circuits. There is always hot, ignition switched and accessory switched all in that electrical center. I just suggest using a slightly modiified $5 trailer brake plug instead of the $50 plug from a dealer.
No sense in sharing/tapping another circuit when they provided dedicated ones already just for purposes like these.
Radio Shack Pro 97 Scanner
Midland 75-820 CB
Cobra 25 NW WX ST CB