I have a Pug Partner van, brilliant van,but has no windows in rear doors, so very restricted rear vision especially when reversing with a trailer,. Thought is to fit a camera at rear to assist with this. Any suggestions for this? I am not concerned with GPs. Apps , recording etc., only something which will do what a mirror would do. Obviously will need a screen on the dash. Is there a wireless gizmo to avoid trailing wires?