Step 2 · Remove Old Trim and Access the Valve
First, remove the old faucet trim. This includes unscrewing the three handles and the escutcheon plates behind them. You may need a Phillips head or flathead screwdriver and possibly an Allen wrench. The tub spout might unscrew or have a set screw on the underside. Next, you must create an opening in the wall large enough to access and work on the valve body and pipes. For a tiled wall, use a grout removal tool to score the grout lines in a rectangular shape around the three valves. Then, use an angle grinder with a diamond blade or an oscillating multi-tool with a tile blade to carefully cut the tile and backer board along the scored lines. The opening should be large enough to comfortably fit your hands and tools, typically around 12 inches wide by 10 inches high. Wear safety glasses and a dust mask.