System 11 and 11A games and their firsts
System 11: High Speed (no multiplexing, five displays), Alley Cats bowler, Grand Lizard (no multiplexing), Road Kings (first YM2151 sound chip). System 11A: Pinbot, Millionaire, F-14 Tomcat (first with four 7-character displays and the FL11630 two-diode flipper coil), Fire!, and Big Guns (first auxiliary power driver board and CPU-controlled special solenoids). System 11B began during Big Guns production, so a Big Guns can have either board set.
Systems
Source: Repairing Williams System 11 Pinball 1986 to 1990, Deel 1, Clay Harrell (pinrepair.com)