Regarding no spark, I would make sure you’ve removed all of the old immobiliser. I traced the wires back from the unit to where it was spliced into and then remade the connection. Good luck.
Again very interesting, along with superb content and quality. More than anything your becoming my favourite RU-vid “have a go hero” Take your time before before the first fire. Great project and I very much look forward to your next post👍………Steve