It would have been either 79 or 80 and would have been Pan Am or TWA to JFK. I also tried Peoples Express as well as AA and, of course, BA. I am fairly certain that those were the days before lounges, as I also remember signing up to BAEC in 1984 when we paid £50 a year for lounge access. My first FFP was AA , around early 80’s.
My fond memory was my first First flight from BOS > LHR on TWA, as no Business was available immediately before Easter 84. I sat next to a very British man who asked if I had been upgraded. No, I said, and “Shit” he said. He then went on to say that his last 8 flights in 1st had been refunded as he had sat next to someone who had been upgraded, and was not of the quality that he expected to sit next to in 1st. I also must have disappointed him as he did not speak again, but I enjoyed the peace and quiet.
I also remember, in the mid 90’s, flying BA Club from JFK to BHX on a 757 where they were trialling the new “bucket seats”. They were, and in my opinion still are, the worst Club seats that BA ever had. On the HK run I preferred CX as they still had “armchairs”, before BA “invented” beds.