Scooterotica

Some will tell you to fit a thinner top plate, but that makes no difference as both thick and thin top plate are retained by the circlip, as the position of the circlip is unchanged then both will sit at the same height.
Sometimes changing the spider helps as this is what position the clip and top plate.

The cut away pics of the clutch are Excellent.

If you've had the piston assembly apart it's possible that the screw/peg isn't fully screwed in and is catching on the rear of the case, had this with my Jet 200 build