Re: Clutch plate setting
To adjust the plate, remove the set screw. You will need to pull in the clutch to make turning the star nut easier. Adjust the star nut a little and release the clutch to feel if the setting is correct. Keep adjusting the nut until the clutch doesn't slip when engaged and doesn't engage when pulled in. Install set screw.
I also suggest that while you're in there to use some brake cleaner on the clutch pads to remove any grease. If the gears need grease, apply a small amount (pea sized).