I put one one my Evolution for the same purpose and got mine from Safety Dave on the internet excellent service and next day delivery. camera for the car and one for the caravan
Camera need to be wired to the ignition,not reverse, so it can be used when you are travelling. Glare does interfere a bit but still good
I have wired my van camera to the vans number plate light, so if I want to use it during daylight hours I just turn on the park lights. This saves runing another power lead from the vehicle to the rear of the van. cheers blaze