How do you install a digital speedometer on a 379 Peterbilt?

To install a digital speedometer on a 379 Peterbilt, first disconnect the battery and remove the existing speedometer from the dashboard. Next, connect the digital speedometer's wiring harness to the truck's speed sensor and any necessary power and ground connections. Secure the new speedometer in place and reassemble the dashboard. Finally, reconnect the battery and test the speedometer to ensure it is functioning correctly.