Model year 1973 was the first year the GMAD buildsheet (General Motors Assembly Division) used the landscape style buildsheet for the Corvette. We know that 1973 was the year we see the GMAD manifest glued to gas tanks. Before 1973, Corvette assembly was under the management of the Chevrolet Motor Division.
Before 1973, the assembly plant used the Corvette Order Copy and copies were glued to the gas tank from 1967 through 1972. Year 1967 was first year build records were glued to Corvette gas tanks.