Original 1963 GMC Truck Dealer Service Manual Supplement. This Maintenance Manual Supplement covers information on the P/PB1000-2500 Models and was meant to be used with the 1962 Service Manual. These Manuals are what the Dealership used to service and repair your truck. It contains information, illustrations, diagrams, specifications and procedures to service your vehicle. Very informative and useful tool for the GMC owner.