You can still cut in Alvin!
I have two of these dome light assemblies, one that works just fine and one that doesn't. It feels like there's dirt or some crud in it when you operate the on/off switch. I'm thinking about opening up the problem one and try to clean it. Tim mentioned that someone did this with some success. It sounded like there's a small ball inside that was cleaned-up, re-assembled and worked just fine? That's interesting the plastic finger was in wrong, a lot can happen to these machines in 70+ years! I'll post some pictures when I get a chance.
Thanks,