I didn’t see Elvis, though I was out in Vegas about that time. (He was sold out.)
I didn’t get to see Johnny Carson either, though he was out there then at the Desert Inn. (If I remember correctly, they were charging $50 to $100 per ticket for him, which I thought was waaay too much for me to spend to see him in those days.)
I did see the production of “Hair” which was also out there. Before the show, the cast members asked if anyone in the audience was from their various home towns. Just by chance, one of the cast members had lived in West Peoria about 6 blocks from me when she was young. When she found out that I was from West Peoria, in the finale she came down in the audience and took me up on stage to dance with her. This is something I will remember forever.