To flip a shower cartridge, you will need the following tools:
• Phillips screwdriver
• Flathead screwdriver
• Adjustable wrench or pliers
• Cartridge puller (optional)
Start by shutting off the water supply. Use a Phillips screwdriver to remove the handle from the valve and set it aside. Using a flathead screwdriver or an adjustable wrench, unscrew and remove the bonnet nut that attaches to the valve stem. Pull out the old cartridge using your hands or a cartridge puller if necessary. Flip over your new cartridge so that it is facing in the opposite direction of how you removed it and insert back into place. Reattach all parts with Philips head screws before turning on water supply again to test whether there are any leaks.