I want to replace the leaky faucet of my bath tub, but I can not remove the stem cover. It seems like the stem cover is part of the stem, since I turn the stem cover the faucet vault can be open and close. I try to pull the stem cover out, but I can not. I wonder if I need a special tool to remove stem cover. Please let know now if anyone has any idea how to remove stem cover. Your suggestion would be appreciated.