Original 1973-82 GMC & Chevrolet Truck Dealer Parts Catalog. This Parts Illustration Book covers the Medium Duty Steel Conventional, Steel Tilt and School Bus Chassis Models. This is what the Dealer used to find Factory Replacement Parts to Repair your Truck. It has Illustrations of the available Replacement Parts with Description and the Group Number to find the Part Number in the Parts Text Book. It does not contain any Part Numbers. It is in good condition with normal wear, blemishing and soiling from use in a Dealership [see photos]. Very rare and informative piece that will be a valuable tool for the GMC or Chevy Truck Owner or Collector.