Since another newbie recently got shocked I'll bring it up: Remember your 110V line voltage fuse is always electrified when the game is plugged in regardless if the master cabinet switch is on or off, I could see how that is easy to overlook down the line. Unplug the game when messing with certain things, the schematic will let you know where that section of always-on high voltage (not a great mix, huh...) is.