Another roadside bodge –*distributor rotor

[AdrianH]

When stranded road-side on Sunday I found my distributor rotor had disintegrated –*the metal conductor had come away from the red plastic main bit. I managed to wedge the conductor back in place with a bit of parking ticket to get the car back to to its house.

So now I've got a new rotor –*how does the old one come off? It seems to be on incredibly firmly, and I don't want to wreck the dizzy just to get the old rotor off. Is there a trick to this usually simply task?