Well, I don't have any pics but I think you would be safe with the original code, the new acrylic urethane or acrylic enamel with hardener will be a high gloss right out of the gun, higher gloss than the original enamel that GM was using. From what I see, they had one black for each year up to 1976.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy