Super C clutch adjustment

I have a Super C that I use to plow and disk a small field to control the weeds (thats what I tell my wife - I really do it just because its fun). Just got done doing the plowing last week and when I started to do the disking I noticed the clutch was not engaging until it was almost all the way out. The tractor also will not stall when disking in a higher gear. If I am in 2nd and the disk starts to bite too much instead of the tires spinning or engine stalling the whole tractor just slows down and even stops with the engine still going as normal. I think that the clutch needs adjusted through the small plate on the bottom of the housing.

Any instructions or tips would greatly be appreciated.

Thanks,

Duane.