Jerry Garcia
- electric guitar (lead), vocals
Bob Weir
- electric guitar (rhythm), vocals
Phil Lesh
- electric bass, vocals
Ron McKernan
- organ, vocals
Bill Kreutzmann
- drums, perc
Mickey Hart
- drums, perc
Information for this event comes from a recent Owsley Stanley Foundation Mystery Reel Preservation Challenge post on Facebook, with a picture of the reel box that says "7/4 Practice" and underneath "John Mayhall". But according to OSF, upon listening to the reel it actually contains a GD rehearsal of the band working out the St. Stephen > Eleven bridge.