That was the ECU finished. The next job was to make up a loom to connect everything together on the car. The first thing I did to achieve this was to position the ECU on the car. This proved harder than thought as the case was larger than expected – or rather the space on the car was less than I thought it was. I ended up with it located almost centrally on the inside face of the bulkhead. The relay board was then placed to the right and a little lower down so all the cables could feed up from the transmission tunnel and connect straight in. I took a length of string and marked every 12” with a black ring of marker pen – one ring for 1foot, two for 2 feet, three for 3 feet, and so on. I fixed the end of this string to the relay board and routed it through the tunnel and into the engine bay. It was then an easy job to route the string to each location that I needed a connection to be made and read off the distance. I noted all of these down and then moved back indoors in the warm!
I had worked out a wiring diagram, the number of wires required and then a colour code for each connection. Starting from the relay board end I ran out the length required to each point (plus a safety margin of 6”) and taped or cable tied the wires (usually as pairs) together to keep things neat. As I worked the list I could group things together that were heading to the same area, the injectors and the manifold air temp for example. After a couple of hours I was ready to put the braided coving over the cables but before that I offered them up to the car to double check I had the lengths right. Using different sizes of braiding I covered each section of the loom and at intersections I finished the ends off with a suitable piece of heat shrink. The final job was to fit the various connectors, mostly two way items that I bought from Vehicle Wiring Products, but also the main connector to the EDIS module.

My initial wiring diagram - PDF