All of the places mentioned by the previous members are correct. I have a 1977 Chevy K30 DRW and the build sheet was in between the gas tank strap and gas tank. I couldn't believe it! I pulled back the bed to do some sending unit work and there it was. It was not perfect but seeing how it was from Nevada it wasn't in to bad of shape. You could also check inside the door panels and on top of the headliner. Not normally a place for them but who knows?