1960 Chevrolet pickup clutch return

[Original60Apache]

So for some reason my clutch pedal won't fully return to the upright position. It's been fine all this time but last night I was coming home and a couple blocks before I got home, I noticed it doesn't want to fully return. It does seem to fully disengage the clutch. It is a hydraulic clutch pickup (60-62). I am almost thinking that mypiston in the master cylinder is what is causing it like it doesn't want to push the pedal linkage to a fully returned position. Please let me know if you have any ideas.

Thanks

Nate