The problem is:
It's too cold where you live.
I spent two and a half years in Anchorage back in the '90s, that was as far north as I was willing to go.
Everything with your speedometer seems like it's working individually, but it clicks at the speedometer when it's put together?
Is the cable engaging the speedometer shaft correctly?
That's the only thing I can think of, especially if the clicking is happening right there at the speedometer.
Maybe the speedometer's shaft is wallowed out?
I'm guessing the issue is up top there because if the cable is spinning, the speedometer should be reading something.