I use my 4 1/2 grinder with diamond wheel to cut the outline of a masonary box(mudbox)
then finish the job with a masonary drill . I use a bosch bulldog , I have a small chisel that fits right into the drill and this works great ! I then pull cable,mc,greenfield etc out and attach to box, then fill entire hole with mortar,then push box back into hole, clean up and touch up around box. wait till set and trim out.
