I'm stripping a set of TT heads for rebuild. Since the heads are aluminum, there appears to be a steel washer underneath the valve springs to keep them from eating into the head. #1- are they press fit in place? #2 if not, how do I get them out? I've tried to turning head upside down and smacking with rubber hammer w/no success. Valve guide and seal prevent access with any magnets I have. I don't want them to come out on their own at the wrong time and getting lost. Any help greatly appreciated.