I have my camera mounted on a small bracket ( which I made ) and it's bolted to the underside of the rear bumper on the passenger side of my tow bar . It's absolutely fantastic for reversing on to a trailer , I can position my vehicle with the tow ball directly under the trailer hitch everytime.
It has also saved me quite a few dollars in insurance claims as before I had it I managed to reverse into 2 other vehicles in tight car parks.
Having it there is the way to go.