You should have two in the 3rd brake light, one for the bed view and one for the digital rearview mirror. Then you should also have two in your tailgate "handle" one is for the hitch view and the other for the backup camera.Mine has both, a camera by third brake light and one also at the tailgate.
This is assuming the tech package you have. But I would think an AEV would have the digital rearview mirror and trailing package.