to my surprise, AE were using a brand new 737-600
Must be a typo there, chevvron.
AE only had 737-200/300/400 (classics)
AE went under in 1991 and the first 737 NG flew in 1997.
So, in 1986 it must have been a 737-200 or -300. The first -400 flew in 1988.