This is a common minor deatail that is easy to overlook, but can make the boat un-steer-able if done wrong. The rudder 'downhaul' must be threaded correctly to make sure the rudder does not kick up while sailing. Even 1/2" of rudder angle can give you so much helm that you won't be able to turn the rudder, or that it will cavitate and fail to turn the boat.
The downhaul must go around the aft most support pin to give it the maximum leverage when the rudder is vertical. In the picture below, the oval represents "the rest of the rudder" (i.e. pretend only the top is an oval, and it goes down two feet).