Valve Seal Removal without damage

Some words of advice if they're used heads you want to go through them to clean them up and look over them... why would you not change the valve stem seals if you're there?

Also just like you do to keep from destroying brand new/decent guides you can take a light file and just lightly go over that top edge of the lock groove on the valve stem then spin the valve as you lightly pull on it to get it out. If it's still fights coming right out then you haven't filed it enough.