Revise laws for agricultural vehicles on the highway

This bill updates Montana laws to improve safety around slow-moving agricultural vehicles on highways. It requires drivers to slow down when approaching these vehicles, matching their speed when traveling in the same direction or reducing speed to half the posted limit when traveling in opposite directions. The legislation also mandates that agricultural vehicle operators pull off the road or onto the shoulder if traffic backs up behind them, allowing following vehicles to pass safely. The law defines agricultural vehicles to include tractors, farm equipment, self-propelled units, tractor combinations, and vehicles hauling hay or straw.