The script is not mine:
local bridgepos = {x=358, y=450, z=9, stackpos=0} -- Position of the bridge tile
local splash = {x=352, y=451, z=9, stackpos=1} -- Position of the liquid pool
local leverUID = 3040 -- Unique ID of the lever
local liquidId = 2016 -- Item ID of the liquid pool
local...