Thanks everyone for your responses. The moment I saw this thread title, I knew that I HAD to reply.
Jim, I'm not mic expert, but I think the clip on mics were small silver lavaliere types, maybe made by Sony? Does that sound right?
Doug, your kind words are much appreciated.
I know I'm repeating myself but looking back, I'm still in disbelief that I was lucky enough to be in on those amazing sessions. I saw Frank Sinatra at the Universal Amphitheater later that year and of course he was terrific, but nothing could match the experience of seeing Studio 1 go from an empty space, to a room packed with some of the most talented musicians in the world, and then watching all those amazing people, with Mr. Sinatra at the helm, record those timeless songs.