I've finally put a bit of time into the wiring - it's easy to get side tracked when there's so much to do. Anyway the wirings almost finished and I'll know soon when I connect a battery if my efforts just go up in smoke!!
This is the Mastercell monted on a hinged plate in the passengers footwell. The 2 connectors receive earthed signals from the various switches and send the message via a CAN cable (yellow connector) to a Powercell module at the front or rear of the car to switch on the the appropriate circuit.
The front Powercell module is mounted on the front of the passengers footwell. The red cables supply current to the module and the yellow connector provides the switching signals. the the outputs go to the front wiring loom via the top white connector.
The rear Powercell is mounted in the boot on the shelf behind the passenger. The red wires supply power from the 4 fusible links on the left. 2 supply the front module and 2 supply the rear. The coil of wires to the right are unused circuits. There are 20 circuits available with the system.
The next step is to take the brave pills and add a battery to the system!!