The faceplate for a bathtub overflow is located on the sidewall of the tub below the faucet. The faceplate may have a lever that controls a drain stopper, or it may be blank. The holes of the overflow that allow water to drain as it rises are usually located on the edge of the faceplate at the four o'clock and eight o'clock positions. A bathtub overflow faceplate is attached using screws or, in some cases, it may be secured using caulk. Removing a faceplate that is caulked will take about 20 minutes.
Spray penetrating catalyst around the entire edge of the overflow faceplate. Soak the edge of the faceplate where it is adhered to the bathtub wall. The penetrating catalyst will soften the caulk and make it easier to remove. Allow the catalyst to soak for 20 minutes.
Score around the edge of the faceplate using a utility knife. Run the knife between the faceplate and the tub, but be careful not to scratch the surface of the bathtub. Make several passes with the knife around the entire circumference of the faceplate with the utility knife.
Slide a putty knife underneath the edge of the faceplate and pry. Move the knife around the circumference of the faceplate and pry in every location. Use the utility knife again in locations that are especially stuck. Keep working the faceplate off the sidewall of the bathtub using a combination of the utility knife and the putty knife.
Clean the area of the bathtub sidewall where the faceplate was located with the penetrating catalyst and an old rag to remove residual caulk and dirt.