Ah, I see. The slot is not symmetrical. So the key and knob only go on one way. And the contact tab only goes on screw stud 9 because the contact band is not 360deg. So it's likely the switch can only be assembled one way.
My switch knob is a modified one, ex BSA I think, which I cut the key slot in, symmetrically - oops!
Anyway I now know that the moulded OFF aligns with terminal 8.
By the way, if you did fit your timing cover, did you manage to satisfacorily seal the generator wiring. I managed to do that a few months ago using a variety of grommets.
Best wishes,
Dave
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