Hi...I know a Wilson football that would have been a 1974 would have had a double "G".....and the codes repeated or reverted back after every 10 years.....so, the G makes sense that it was a 1984. I think the second letter has to do with the month of manufacturing. Also, after the late'70's, Wilson dropped the trademark below the "N" in Wilson......so this is definitely post '70's...... Hope this helps.....