Are you making sure to hold the clutch lever arm up when making the adjustment with the screw on the side of the case? In other words, hold up the lever to the point where it stops. then (assuming the mark is not lined up, screw in or out to get them lined. (so the mark on the arm and the case are lined up).
If that was already addressed the next thoughts are:
With wet clutches we always have to ask what oil are you using? This can end up being 3 things together. Oil, spring, plates.
If I had the same issue, honestly I would replaced both based on what you have done. Also the gaskets can be found. :
http://www.bikebandit.com/athena-complete-engine-gasket-kit?m=9230I would order the whole set. (if you plan on addressing other things later, it wouldn't hurt to have them ready, and you save).