How do change a speedometer in 1990 Dodge van?

To change the speedometer in a 1990 Dodge van, start by disconnecting the battery to ensure safety. Remove the dashboard trim and unscrew the instrument cluster to access the speedometer. Carefully detach the speedometer cable and remove the old speedometer from the cluster. Install the new speedometer, reconnect the cable, reassemble the cluster, and replace the dashboard trim before reconnecting the battery.