I'm trying to replace a fill valve. The existing one, the part where the supply connects, which passes through the tank, is metal, as is the nut which secures it to the tank - and what do you know it's siezed. It spins freely in the hole in the tank, but it will not budge when I hold it. Any good ideas on how to remove it without destroying the tank?

I am having a difficult time trying to find out how to remove a bathtub faucet handle. The only thing readable on the cover is "niedecken" and "Kohler". It is similar to a hotel tub handle - long, single handle that turns clockwise. There are 2 screws that hold the cover behind the handle on. And one large screw into the center of the handle. The two screws release the cover, but the handle screw does nothing to release or loosen the handle (the size of the handle prevents the cover from being removed). I have turned off the water and tugged on the handle. Tried turning the handle as far clockwise as it will go. Can anyone provide the proper way to remove this type of handle? When I tug on it, it sure feels like it's still connected to the plumbing behind the wall. There does not seem to be any kind of "button" or release point anywhere on the handle. Thanks so much for any help.