Even though it does not have SCV '74, which was my original motivation for buying it, I still like the McCormick tape because, obviously, '73 was a great show, too. Plus, the tape has Stan Kenton praising drum corps, Royer saying some interesting things (and asking the older kids to take care of the young ones - very cute), and with the fan and corps member interviews, it really takes me back to that era. The cover of the tape is bizarre, though . . . it has a picture of what looks like a Marine D&B Corps drum major on it.
Thanks to all who answered regarding a tape of the '74 show. I'll follow your leads.