Take your reverse camera and insert it in to the camera mount. 

Take the clamp plate and place it behind the camera. 

Fasten the mount and clamp together using x2 M5x12 button heads and nylocs.

Take the camera mount and bolt to the bottom of the tray using x2 M5x16's and nylocs . 

Plug the camera back in and angle the camera down towards the tow ball. 

Cable tie the loose reverse camera loom to the tray away from any hot or moving parts.