I printed off the internet the part breakdwon to my tub/shower one-dial Symmons Temtrol kit as I am trying to stop a slow leak out oif the tub faucet. I removed the screw and cap - and I can't get the handle off - is it hyst suppoosed to pull off once the screw is removed? That is how the instructions make it sound? I don't want to force it case there is some trick to it... any suggestions - I think it is just stuck and needs some persuasion