1/ The only spec I have on that is from Hobie 20's. Same ball system and mast base. 1 7/16"
2/ Tension the striker till the slop is removed. I wouldn't tension much more than that.
3/ Rudder rake standard measurements as I recall them: Measure, from the bottom of the rudder casting, down 12" and make a horizontal mark on the blade. Measure, from the front of the blade on the horizontal line, back 1 3/8" and make a vertical mark. That mark should be on the center axis of the rudder pin for a balanced blade with slight weather helm. You can pull a line (snap line) along the center axis of the rudder pin and see if the mark on the blade is positioned properly. Be sure you still have a slight weather helm feel when on a reach. You do not want a neutral or negative pressure on the tiller. That is dangerous and difficult to control.
That all I have.
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