The closest I have come to seeing Chuck was when his cousin Marvin Berry called him as McFly played Johnny B. Goode at the Echantment Under the Sea Dance. (see avatar)
I've also seen some good footage circa mid 80's with him jamming with Keef and drummer Steve Jordan. That's been on TV several times, so I'm betting many others have too.
All kidding aside, it's great Chuck can still get out there and play. The first cassette I got as a kid, was his Greatest Hits and it inspired my first Harmony acoustic.