Step 5 · Remove the Main Drain Body from Shower
Return to the inside of the shower. The drain body should now be loose. Try to pull it straight up and out. If it is stuck by old putty, you may need to twist it. If it won't budge or is a screw-in type, use a drain wrench (also called a dumbbell wrench). Insert the appropriately sized end of the wrench into the crossbars of the drain and use a large wrench or screwdriver for leverage to turn it counter-clockwise, unscrewing it from the lower assembly.