Search for the right threads, this has been covered several times. In short the mirror plug or overhead light harness are options, but I'd just run it down the a piller to the fuse panel to keep it separate without hacking up the factory wiring.

 

Just in case you are planning on hard wiring the power cable to 12 volts please know that the dash cams and all other devices that use that cable are 5 volts.

If you hard wire it and input 12 volts it will fry, make sure to use the power adapter that turns 12 volts into 5 volts.

 

Installed a BlackVue 750S a week or so ago. Ran wire down passenger side headliner and pillar to the fuse panel. Used add-a-circuit deals that came with the camera to tap into the switched and constant power sources needed. Looks good and clean and functions as it should. Note: I also have a Power Magic Pro to monitor battery life and timing of the camera.

 

Definitely the best way to do this is to use an add-a-fuse at the fusebox in the passenger kick panel. You'll have to dig and test a bit to find a bay that is ignition triggered, and is free (although I think some add a fuses allow piggybacking). Just make sure you get the correct add a fuse, these trucks use Micro, not mini. I would tell you what mine is plugged into, but I think the fuses are different depending on the truck config, and I can't remember. It takes 10 minutes to find one

 

I just made a simple connection for now - used one of the USB ports. My dash cam uses a mini/micro to regular USB cable and came with a 12V adapter. I was happy to find that they are switched - dash cam goes off and comes on with the truck. Not the best solution but I have the cable mostly hidden.