48v Gem e825 golf cart

Just received a 48v gem golf cart. Serial numbers missing, it’s in great shape. My problem I don’t have wiring schematic for batteries. I can wire to last battery, have checked voltage. But don’t know which wires outta dash go where. They are tagged battery 12v, 36v -, 48v - 12v +. I know it’s something simple but need little help