Megajolt E
 

I'm thinking about putting an order in for my megajolt but do I also need the harness kit they describe (either basic or deluxe) ? http://trigger-wheels.com/store/contents/en-uk/d59.html

I made my own engine loom for my Megajolt, using the donor Sierra (mine was also a 1.8cvh). It had all the cabling in I needed (shielded etc) and cost nothing. I got my edis 4 with plug off ebay for a fiver and the diy megajolt kit (c/w cables, plugs and hard rev limiter) from the states for around £100 at the time.

Looking at the website, it doesn't look like you can buy the kit anymore :-( But if you have the donor loom kicking about and your handy with a soldering iron, I'd leave the harness.

Well my engine was a 1.8 cvh cfi, so it already has the trigger wheel, crank sensor, coil pack, edis4, spark leads etc. So I guess all I have to do is seperate out the right wires out of the donor loom I have and instead of them going to the old donor ecu, they would just go to the megajolt instead? And all of these wires would have the right sheilding etc?

You don't need the harness kit. As your old loom will have more than enough of the correct cables you can reuse to wire the megajolt.

One thing I noticed with mine, was that the PIP & SAW wires that went to the original ecu did not have the cable shield connected to the EDIS. I ended up having to strip the loom down a bit to connect the shield as shown on the megajolt website.