I phoned 1-800-222-1020, (Chevrolet Motor Division) and ordered my FREE Restoration Packet. All they wanted to know was year of my vehicle, VIN # (I guess to verify year), and name and address to send the packet. I got a TON of free information on my '56 3100 (this is infromation taken from assembly plant details), as well as a booklet that listed a large number of parts suppliers and publications. (Did I mention it was FREE?) Highly recommend this packet.
I have one also, for my 52. It's nice but being copies it is rather hard to read as it is not the clearest and best copy job. But the price was right.
RE: Chevrolet Restroration Yes and if you want to get a packet for a GMC it will cost you $25.00 but it's better than nothing. The number is 1-800-467-6853