This is interesting, old invoice documentation from GM

I found some information on the NCRS tech discussion forum that GM offers a service supposedly free of charge that you can order a copy of the original invoice from their records warehouse. So I sent an email to Peggy at GM, peggy.vezina@gm.com I included in the e-mail the model year, make of the vehicle, the VIN #, and my mailing address. Based on what I have heard, this service is available for models maybe as far back as 1975.

Here's hoping! This would be a nice thing to include with the resto.