What I have done before that works well for me is to first pry the box away from the stud using a screwdriver. You only have to create a small gap between the box and stud. Then I use a sawzall and cut the nails holding the box to the stud. Next carefully pull the box and wire out of the wall. I usually don't have too much trouble doing it this way.
#37928 - 05/11/0411:35 PMRe: removing new work box
... If the wire is Romex,and the old box is metal,you can substitute the box with a plastic cut-in,because they're usually a tad bit larger,and you can cut the wallboard open in order for the plaster ears to be snug against the wall material,..then tighten the hold down screws with the wing brackets and you're done..Available in single,2-gang,3-gang as well..Plastic boxes allow more volume capacity,as there's no clamp for de-rating.. Russ
[This message has been edited by Attic Rat (edited 05-16-2004).]
.."if it ain't fixed,don't break it...call a Licensed Electrician"
#37934 - 05/16/0403:11 PMRe: removing new work box
I found it easier to use diagonal pliers to cut the nails(on plastic boxes). I always used them to pull the cut end of the nail out of the stud too. As to the why...to replace a single gang box with a double gang when the customer wanted a ceiling fan installed in place of the ceiling light.
#37935 - 05/16/0406:35 PMRe: removing new work box