Backup light power wire, anyone know?

I just installed a back up camera with my Jensen 9512 head unit. There are a lot of threads that say people have done the install and just connected the backup camera to the backup lights but they don't say what color wire it is that they spliced into. Does anyone know which wire it is that I'm looking for? Its gonna be the 12v wire that is hot when you put the truck in reverse. I found the wire harness that goes into the backup ligts but I don't know which wire it is that is supplying the power. Any help would be greatly appreciated. Thanks.

 

Found it. I tapped into the rear hitch power adapter. It was the center connection that was powered when I put it into reverse. I believe that it was a yellow wire. I used a quick splice to tap into it. Now my backup camera works great.