A Ford dealer can sell you a replacement backup camera that plugs into your F-150 wiring harness. It costs around $50-60, if I recall correctly. You can then drill a hole in the rear bumper where the license plate goes, install the camera there, punch a hole in the license plate where you mounted the camera, and reinstall the license plate. I had this done on my F-150 two years ago and it works fine. It works so well I don’t bother to reconnect the tailgate camera when I put the tailgate back on.