According to Harry's friend, Michael Macaluso, while the two were grabbing a bite to eat at Martoni's they ran into Rob Reiner who invited then to be a part of a concert he was filming for a rock movie. They didn't go because of a previous commitment. Later they learned that the film was This is Spinal Tap.
Harry was one of the sharpest, smartest, creative souls ever (even with his drinking/drug excesses). A real friend he was, I miss him dearly!
-- Michael Macaluso
-  Source: Facebook Post