Where to pull power for bed accessory?

I’m looking to tap into something in the bed that would preferably be getting power only when the ignition is on. Any wires in the tail lights, bed lights, or trailer wires I can pull from? Or even if it’s just constant power I can use too. I have a wireless cb radio im looking to power up.

 

To be honest, I would do it “correct”
Run from engine bay with fuse and relay.
Heavy enough gauge to the bed that you could then wire up what you need .
Just me 2 cents.

 

If you have the 7-way plug for trailer wiring, one of the pins is keyed 12v. I don't remember which off the top of my head and too lazy to find it. Sorry.

 

Taillight circuits get glitchy when resistance in the "dissipated but still connected" circuits changes (LED tailight bulbs replacing halogen, etc). And you do not want to overdraw those taillight circuits. As stated ... make a dedicated line or tie into the line for the factory bed-outlet.

@caribe makaira would know which wires in the towing harnesses would work ...

 

Also, for your cb, you could run a relay and fuse, and use a dedicated power switch
It’s pretty handy and you can get a Toyota style switch for it.

 

the +12v wire in the 7-pin(on the diagram on the cover) is set to only come on with the engine running.

that's on a relay under the hood in a 'side-car' box to the fuse box. could alter that relay to be on key instead of on engine-running, and then use the

$38 curt 56584 replacement vehicle-side custom USCAR 5-pin trailer wiring harness , black

curt 56584 adapter harness as a sacrificial wiring harness to cut up without altering the vehicle wiring.

 

I mounted distribution blocks(2) in the engine compartment. I ran fused red and unfused black #10s to the compartment in the bed area to 2 blocks. I tapped off that for switched bed lights. I also ran another set for control of the tailgate. Run them together to save time in the future.