Ready the opening: Apply a thin layer of compound around the perimeter of the hole. Then you can simply mud over it. I need to move this to center a new. After rewiring, addressing multiple outlet holes left from decommissioned junction boxes can be achieved effectively. For smaller holes (up to 6 inches), California patches are recommended. Apply spackling compound with a. In this video we look go through the process of patching old electrical boxes, 7 in 7 minutes To see how to finish the patches check out - • A complete guide to Patching a Hole in Dry. Sometimes they are called "Jumbo" plates.