Did the clash open for that one?
Yes. One of two times that I had tickets to the Clash and missed them. It was a Friday night and traffic was a mess from Orange County to LA - we arrived late(ish) and at the time I really wasn't that into punk as much as following my folks roots in classic rock. The Clash had already started when we arrived, and we stayed in the parking lot so my parents and their friends could get stoned before we went in. I heard a few songs from the lot, but truthfully, I only knew what the radio played and wasn't pushing to go in - a few months later I would get more heavily into them...
...which leads to the second time I missed the Clash. US Festival, 1983. Yes, I had tickets to Mick Jones last performance with the Clash but we left early. If you couldn't tell by now, I grew up with pretty cool music parents. They went to the 1982 US Festival without us, but took us in 1983. On Saturday, it was all the 80's KROQ bands with the Clash as the headliner. The show is cruising along and we're having fun, then the Clash don't come on. An hour goes by, people start leaving as rumors are circulating that they're not playing. My folks take us back to the camp ground and about 2 hours later they finally come on and we can hear it, but couldn't see it. There was some fight with Wozniak about ticket prices or amount paid or something, but we walked out after waiting an hour. A few months later Mick Jones leaves the band I never got to see them.
The next day I saw Van Halen and the day after that I saw U2 for the first of many times (Bono climbed the rigging during Electric Co and it absolutely blew away 10 year old Smackie) and many other awesome bands, but I failed to realize how much I would regret leaving that Clash show. That 1983 US Festival was a defining moment for Smackie, both good and bad.