I got the answer I was afraid of. The drive gear for the speedometer is plastic, and since the post that turns the cable doesn't actually turn, the drive gear is a goner. This is on the car that I did the drive train swap to, and am selling. The new owner will have to decide how bad they want a speedometer, since it requires either opening the transmission case to get at it, or swapping in different used tranny. Here's the thread on that car:
drivetrain swap fun !
Anybody need a winter beater ? I'm asking $1900
In case you notice that I mentioned the speedo working at one point in that thread, I swapped out the first tranny because of a viscous coupler issue. at least the second one I installed was free !