There were 2 different cocktail cabinets available for this game. The 2 cocktails seem to represent 2 different generations of the Sega/Gremlin cocktail, the only differences between them are the control panel and coin mechs (Both cocktail cabinets were also used for other Sega games such as "Frogger").
The cocktail versions used small 13in. monitors and were relatively unadorned. The older ones had a larger control panel and different coin mechs. The only decoration was a set of instruction cards underneath the top glass (the cards were the same for both versions). These machines used small 2-Way joysticks for movement (instead of push buttons).
The upright and cocktail versions of this game used 2 different sets of PCBs. They both use the same wiring harness, but the cocktail version flips the display for the second player. This is a bit of an anomaly, usually games simply have a switch on the mainboard to switch between upright and cocktail mode.