How To Remove Metal Electrical Box From Wall. Untwist any wire connectors from wires inside the box.; If the box is installed in the ceiling, two nuts in the top of the box may be holding the box in place.
Look inside the metal junction box for where the wires enter.; Disconnect the circuit cable from the electrical panel if you don't plan to. Make the hole dimensions 2 or more inches bigger than the box so you can access the nails holding the box to the wall.