well you have the clutch operating arm which goes down into the case, around the shaft of the operating arm there is a groove, this groove is for a locating screw to keep the operator in position and stop it from rising up when the clutch is operated,
also the operating shaft had a flat side towards the bottom half, this flat presses agains the pushrod and therefore moves the rod and opens the clutch plates against the tension of the springs
this is how mine are and i guess yours will be similar....learn to post pictures!