I have a series 2 1974 M reg and I'm going to fit an electronic ignition kit. When I unclipped my cap it has an extra piece between it and the distributor, a kind of centre ring. (Does that make sense?) The points wires connect to the inside of the centre ring. Is this a Lucas ditributor and would it be the 25D? It's in such an awkward place it's difficult to find any distinguishing marks, and it's pretty grubby too.
Thanks in advance for any help,