From ipdb.

Grand Lizard' is one of three Williams games that went into production using System 11. All three games have incorrect schematics showing the same error by depicting placement of the flipper end-of-stroke switch on the wrong side of the coil. As far as we know, all games left the factory correctly wired for EOS. Only the schematics were incorrect. No Manual Amendments or Service Bulletins have been found that acknowledge or correct this error. For a correct drawing of EOSS placement, consult the schematic for Williams' 1986 'PIN·BOT' or subsequent Williams games.

Are you sure it's not the upper flipper EOS. Because the cabinet button should be the flipper and magna save switches.

Or that switch is the magna save switch.