Hi, Could someone tell me what the numbers/letters mean that are stamped on the rotor&stator please.The ones on my 1970 rt1 are FZC-1A1L. G-6 which is the ones in the parts book. I also have a spare pair that are stamped FZA-1B/L. E-1 ( rotor) &FZA-1BL E-3 (stator ). Are my spares compatible. All help appreciated . Thanks Alan.

I'm pretty sure your spare set is from a DT1.  Not sure what you mean by "compatible"?  If DT1, it should "bolt on" and work just fine if you use the set...  I wouldn't do something like just use the flywheel from another set.  

If you reach out to member DEET I'm sure he can explain the differences.   

Do either of yours have the mechanical centrifugal advance ignition timing mechanism?

Good point #3 if advance the points sit further out on the plate due to a fat cam on the 360 advance flywheel. Mind you the advance flywheel isn't flat across the face like all the others & is slightly but obviously convexed "not flat" slightly stepped.

The main reason for the question was the numbers on the spare set being different ( e-1 & e-3 ), as apposed to g6 on the original one. The g6 one has the advancer on it so have to remember to set it. Very similar to pre unit Triumph.  Again thank you everyone for your answers.  Alan.

Just to confirm, the stator plates are different and not interchangeble with the different rotors. The rotor with the mechanical advance must have the corresponding plate.