Mine started the same way about this time last year. Ticked intermittently for a while, then one cold Feb morning, it started screaming at me about halfway to work. And I mean SCREAMING
...Ended up pulling it and it was the gear mentioned earlier. I sent the whole cluster to Williams Speedo in AR and they did a perfect job, including replacing bulbs and repainting the needles. The only thing I was a little disappointed about was some dust they left inside. Had to take it back apart and clean that myself before remounting. Can't remember now what it cost, but I can find the ticket/phone if you need it.
Side bonus was that my ACC started working again perfectly after the rebuild. Oh yeah, they tag it with odo reading and service date so no questions come back to haunt you later.
TC