My husband actually has the boarding pass from that flight. I don't remember the date but it was March 1991. NW was offering upgrades for full fare coach pax. He really thought he was something sitting up there. It was DTW-DCA.
I was going home SYD-HNL-LAX-DTW-DCA on day and he met me in DTW. He asked me to marry him in the F concourse just before I got on my flight. I ended up sitting in FC next to Alice Cooper. He graciously listened to me babble on and even showed interest in my new diamond.