How do you change the temperature gauge in a 1998 Chevy 2500 Express van?

To change the temperature gauge in a 1998 Chevy 2500 Express van, first disconnect the vehicle's battery to ensure safety. Remove the dashboard panel to access the gauge cluster, then unscrew and detach the temperature gauge from the back of the cluster. Replace it with the new gauge, reassemble the dashboard, and reconnect the battery. Finally, test the new gauge to ensure it functions correctly.