Great pic, thank Mr. Tourist!
Now 40 year old memories being what they are, I'm reconsidering this. I think what may have struck me about Charlie on stage that night was that he was not wearing a tie or jacket, was out of uniform, so to speak. The live clip of Panic In The World I remember seeing on TV that spring did feature a guy with long, straight hair obscuring his face, IIRC, but one who rocked his head just like Charlie is in this video:
https://www.youtube.com/watch?v=2coXmGHIZbQ
Could be he was wearing a wig for laughs.
This video is a revelation, to me, BTW, I've never seen it before and am bowled over by the sharp picture, sound quality and length. IDK if it's been posted here before, but if not it certainly will be appreciated.