Thanks gomog,
In response to the technical details of the engine stop/start, it was occurring under the following conditions :
> engine at operating temperature (probably 10 mins after starting)
> engine revs at >1500 rpm, and especially around 1800-2000 rpm
> she was however able to idle
When the engine stop/start occurred, it was during normal driving, with the clutch out and in gear. The tacho would drop to 0 rpm (engine stop), but then would immediately power up again, causing the tacho to jump as the engine turned on again (like a clutch start)
I did think about checking whether the engine would do the stop/start when not driving and at 1500 rpm. However the replacement of the ballast resistor and coil last night appears to have achieved the recommended impedences and voltages, and more importantly she is running again.
As I mentioned originally, I have a steep learning curve when it comes to all the mechanical and electrical issues with carby / distributer engines. Although I now have picked up some info re the coils and and ignition modules, distributer timing does appear to be more complicated, and I will leave this until I need to learn more.
Thanks again, Barney
