(Please note that American Airlines listed both Boeing 737-200 and 737-300 equipment as “73S” in the August 1988 Official Airline Guide.)

American Airlines Boeing 737-244, N754UA, is shown at Seattle/Tacoma on May 24, 1990.
(Photo credit: Aad van der Voet via AirHistory.net)

American Airlines Boeing 737-34A, N676AA, is shown at Orange County in August 1989.
(Photo credit: Frank C. Duarte, Hr.)