Got this from a PDF I was given when I picked up a neglected CB500 a few days ago. It's an almost-500-page book with all the details of all the bikes up to 1998. The whole thing is 149MB so I can't attach it here and it's too big to go through email.
I extracted a few pages with 750cc models as a sample. But there's so much more: all the official model names, index by frame number (up to 1980), index by VIN (1981+), explanation of model names, etc.
Mods, please let me know how to get the full document to you. Hopefully it's worthy of going on the manuals & documents page.
Enjoy.