Just thought I would share this YouTube video to add to the knowledge base of this thread. I found it when I was getting ready to redo the vent windows on my 68. It specifically covers restoring a 67-72 vent window, but most of the stuff applies to other years. It's very in depth and helped answer a lot of questions. The only thing I did different was to drill out the 2 rivets holding the vent window pivot on. I chose to do it that way because the original rivet is stainless and the replacement rivet is galvanized. It adds a little more time to the project, but I thought it wold be worth it in order to have the factory pivot rivet.
https://www.youtube.com/watch?v=WiZOiHmcb_w
Rob