Ah, it seems the coil (made by Ducati!) died on Wednesday.
So off came the flywheel (also made by Ducati!!) - points checked, condenser
replaced and coil replaced. At least I've got a spark now!
Changed the fuel for some fresh stuff and, after half a
dozen kicks the beast came to life!! It's a little rough, ticking over
really high and utterly gutless but I still have to clean the fuel line and
stop cock, and set up the carb. However none of this stopped from
going for a little ride!!