After installing my transmission ( Muncie 4 speed) after a clutch change, my speedometer did not work. It took me awhile to find the problem but it resulted that the cable connector had slipped up the cable shield when I removed it such that the end of the cable end was not deep enough into the transmission to engage the cable.

The transmission end speedometer connector is crimped to the cable shield. On mine, the cable connector was not crimped enough to keep the cable from slidding down the cable. I positioned the cable correctly to the connector and recrimped it. This solved my problem.