Welcome to the forum from California.
Keeping what Jason said in mind, start checking the basics. Check fuses, bulbs, the instrument cluster ground connection to the cab sheetmetal on the driver's side, electrical connections between the wiring harness plug and the printed circuit on the back of the cluster - make sure the harness plug is seated into the cluster housing, check the electrical connections between the gauges, gauge sockets and the printed circuit, check the dash light dimmer control, etc. There's a good chance you have burned bulbs and multiple connection problems. Be careful cleaning the printed circuit, because the foil will peel from the flexible backing easily. The odometer not working is a mechanical issue.