Well, yes, I was there. The really weird thing today is getting anyone to believe this really happened. The story given out at the time was that the Dead came in on one airplane and their equipment, on another plane, didn’t. So, they borrowed some equipment from a “local band”. After playing for a while the “local band” came up and jammed for a real long time; very cool.
It’s worth while reflecting on the Sports Arena as well. This was where wrestling events were held before wrestling was ‘cool’. It was big enough for a wrestling ring and what I recall as roll-out stands like were in my high-school gym. Only of course those were around a basketball court (rectangle) in high-school, not a wrestling ring (square). The point of this is that the Sports Arena was about 2/3 the size of your high-school gym. They disappeared the ring and rolled back the stands and let the good times roll. With the Dead. With the Allman Bros. Oh yes.