Wow. That is great that you got it working. Making sure the wires aren't hooking up the spark plug wires in reverse order is not something that would be part of the troubleshooting. That is an easy fix, but not something that is easily identified. Glad you found that and got it all running! Good job!OK, sussed it. When I installed the loom, I laid it where it suited the car best, along the lhs of the engine. So the branch of the loom that fires the coils was left to right instead of right to left. All fitted up and clicked into place perfectly.
When I go to start it, it runs OK for a second or so, obviously wasted spark until it gets a cam sensor signal. Once it gets that, it goes to exactly 360 deg out of phase. 1 gets a spark when 4 should, etc.
Fixed in about 10 minutes.
Thanks for all of your help. Greatly appreciated. M