Problem fixed (well...almost)
I got a second hand ignition module today, plugged it in and the car started straight away. Haven't replaced the green wire yet. Drove around the block a few times, then I noticed the RPM would drop very low (but didn't stall) when idle in gear or A/C swtiched on, which wasn't there before. But at least she's now drivable!
Thank you all again for your help, deeply appreciated.