Starting on the wiring, probably the biggest headache of the whole project.

I have obtained a front and rear wiring harness from a '96 Miata. I have started to strip off the tape and plastic forms and have started to identify and tag the various connectors. Not all of these wires will be used, only those that control the engine and its subsystems. I will use the Caterham wiring for the rest of the car. I am using Mazda wiring harnesses because I am using a Link Engine Management system which is a stand alone ECU designed for the Miata engine. It fits into the factory ECU box and connects directly to the Mazda wiring harness. It has dual processors and allows control of all ECU functions including timing and fueling in 96 zones. I use a similar Link system on my Miata and am familiar with it. Flyin Miata provides excellent software and product support for the Link.

This is the harness between the ECU and the main harness. Most of these wires will be used, all of them will be shortened and spliced unless I decide to mount the ECU in the boot (trunk).

The rear harness that comes from the Miata battery which is located in the trunk. I will shorten this as the Caterham battery is mounted up front. The black box contains relays and fuses and I will use it on the Miata.

The main harness from the Miata. Most of the unused wiring and connectors have been stripped off and the remaining connectors identified and tagged. Those connectors and wires are shown below in the box. This collection of discarded wiring and connectors will grow.

All three harnesses at once except for what has been removed and in the box in the previous picture. Still a lot of work to be done before it is ready to test fit to the chassis.

Still to come, the engine and injector harnesses. They are ordered and on their way. They are relatively small compared to the others and will be used with little modification.

The start of this project is here