Speedo Question

The speedo in my '72 has started making little stuttering
movements accompanied my small noises. Very distracting.
Can someone point me to info on how to clean and/or lube
the internals? I have the speedo out and out of it's case,
but I'm not sure how to proceed. If I remove the metal face
plate will I find some gears to lube?? Just does not look like
that from here. The cable is only several years old, dating
back to the 5-speed job so I doubt it's that.

chuck