How to fix 66 Cuda Tach?

They are only a couple hours east of me. I believe they are in Harrow.
That’s a great website that I’m glad to have learned about. I sent them an email, and I’ll report back with their reply.
Thanks!

They rebuilt/restored a couple of '67 speedometers for me and did really nice work. It is a bit of a pain shipping-wise because they are in Canada, but very affordable otherwise.