I bought a used 06 WT and the tailgate bezel was broken off like so many you see these days. So I took advantage of that. I got a good camera, glued on a strong magnet from a salvaged harddrive and then it just sticks on the metal under the handle as you see in the pix. I'd be first to admit that looks like a shadetree setup. The photo makes it look worse than it is from a distance.
I also added a small slide slide switch in an unused plug on the dash so I could turn on the camera whenever I wanted rather than tied to backup switch.
I ran the wiring by drilling a small hole in the grommet for the gear shift on the driver side floorboard. It was necessary to run the power with ignition on along with the video cable since you can't pick that up in back.
A big advantage of having the camera in that handle is that when you put the tailgate down you see straight down to the trailer hitch. Very useful.
BTW, don't buy one of those cameras that mount on the license plate, they are not waterproof and will eventually fog up or show droplets inside.