A day after the trauma of the breakdown on the way to Wheels Day, the investigation began!
Still refusing to start and having no spark I decided to swap in a known good coil, lo and behold the car started and I was able to reverse out of the garage having to push in the day before.
After letting the car idle for about 10 mins it decided to cut out and refused to restart.
Knowing that the Pertronix is very sensitive to correct voltage I decided to charge the battery, however the car still failed to start and still had little or no spark.
So the decision to go back to points is confirmed and the parts are on order from O’Neills