Info on how to remove the finger wheels from Western Electric phones can be found here. This is mainly for the 500 type dials/finger wheels.
http://www.porticus.org/bell/telephones-technical_dials-rotary.html ( dead link 2-21-2019 )
https://www.telephonecollectors.info/index.php/search?q=remove+fingerwheel (https://www.telephonecollectors.info/index.php/search?q=remove+fingerwheel)