Newbie here...can't get clutch to disengage...

The problem might not be the linkage. It could be that the nose of the tranny input shaft is binding in the pilot bushing (in the end of the crank) and then the input shaft doesn't stop turning when the clutch is disengaged. Did you have any problems, as far as things being tight and not wanting to go together, when you bolted the tranny to the bell housing.

Terry