I have a Eberspacher heating system fitter to a Land Rover TD5 Defender Ambulance it has a temperature regulator in the cab which regulates the heating in the Ambulance part of the vehicle but the problem is when you sleep in the back you are unable to turn the temperature up or down because the switch is in the cab what I want to do is fit a second regulating switch in the rear that can be added to the system to be controlled in the rear box but will allow the cab switch to work alongside it. Steve