Hi Ron,
The speedo is fed a signal that comes out of the tail section of the transmission. This wire travels up into the cabin and into a connector on the left side of the transmission tunnel. A wire exits this connector then goes up into instrument cluster via a 6-pin connector on the back of the speedometer.
What I would do is make sure you have power and ground at the 6-pin connector that plugs into the speedometer unit. This provides power to the speedo/odo and ground to the entire cluster.
Do any of the other gauges work?
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