Steps:1. Put on safety glasses and pry off any trim blocking access to the panels using a pry bar and hammer (figure A). Be careful not to break your trim.
2. Remove panels adjacent to the opening so you can fit a replacement. Begin prying out the nails holding in the old tongue-and-groove panels. Slip out the piece and repeat as often as needed (figure B).
3. Measure the size of the opening for replacement panels. If there is an outlet or other electrical fitting, measure the exact position so you can make a cutout in your replacement piece.
4. Transfer dimensions onto new paneling piece using a carpenter's square to mark cutout for box. Drill holes inside the cutout area for the electrical box using a paddle bit. Insert blade of a jigsaw through holes to cut out area (figure C).
5. Cut remaining pieces to length with a circular saw.
6. Slide replacement pieces into place, making sure the tongue-and-groove pieces fit together tightly (figure D).
7. Drill pilot holes and secure each piece as you go by partially driving in nails. Once everything fits back together, drive the nails all the way in and set below the surface using a nail set (figure E).
8. Reattach trim pieces. Use a shim if necessary to get a good fit between the trim and paneling.
9. Cover the junction box by screwing on the plate.