A Rockwell shower faucet is designed with a handle and stem, like many other types of shower faucets, so it is removed in much the same way. The process requires few plumbing skills, most of the work involves turning the right wrench and knowing which parts of the faucet to remove first. If you ever have to replace one of the stems in this type of faucet, you will remove most of it in order to access the stems.
Shut the water off by closing the main water lines running to the home's water heater.
Take the cap off the top of the faucet handles with a knife or flat head screwdriver and unscrew the screw below the caps with a Phillips head screwdriver. Pull the handles off by hand, or attach a handle puller to the handles and turn the handle puller post to extract the handles.
Take the stems out of the handle pipes by rotating the stems counterclockwise with a bath socket wrench. Turn the stems until you can pull them off by hand.
Remove both seats, the small valve heads inside the pipe handles with a seat wrench. Turn the seats counterclockwise with the end of the wrench in order to remove them.