What kind of clutch are you running? My new Centerforce is pretty easy, but don't think I could disengage it with my hand. Sounds like you have too much lash in the pedal. Did you adjust the lash with the pedal up against the stop? Are you sure the fork is properly engaging the T.O. bearing?(i.e. fork spring
inside the lip of the T.O. bearing?) Is the fork properly engaging the pivot ball on the bell housing? Are the flywheel & pressure plate housing bolts tight?
Just some things to consider.
http://kurtspontiac.homestead.com/TimSimpson66GTO.html