1965 Chevy C10 - instrument cluster blues

[jocko]

perhaps broken driven gear - sounds like it's still "kinda" attached in the dash or the speedo needle wouldn't float. But the fact that the odo isn't moving has me puzzled...

I would think that if the odo isn't rolling at all (and it just started NOT moving when the speedo needle started acting weird) that the speedo needle wouldn't be moving at all either. I'd assume a broken odo if it were just the drum, but speedo and odo going weird (speedo) and dead (odo) simo has me stumped.

I'd check the speedo cable connection at the speedo first, then at the trans - and look inside the speedo grar housing to see if any teeth are laying around. Frustrating - yes!