DR George, additional thanks for the link to the MET Gala for Rudolf Bing.
I watched it live at a friend's house somewhere in Cleveland Heights, and bought the Deutsche Grammophon LP as soon as it was issued. Yes, I still have it.
It's amazing to think that the telecast was never preserved in any professional way, and I believe this version, while close, is still not complete. But how great to see and hear those incredible singers who [a few of us of a certain age] knew and took for granted.