Saw ELP at Cornell University's Barton Hall. Late 70's, maybe 1980. One of the Crazy shows that you tend to remember. General Admission, 2nd row seats, opened with Peter Gunn and Blew the roof off for the next 3 hours.
I'm not a huge Mule fan but I saw their Pink Floyd tribute tour and they were damn great. They even gave Gilmour's show a run for his money except in the lighting area.