If your in the area, swing in, I'll make you 2 pvc plates that have a slot and nylon screw, ten you can addjust....
Didnt you notice that small clicking wheel on the side of the pivot? turn it one way, it forces the float down, meaning it maintains a lower water level, the otherway, an it relaxes it and allows for a higher level... why dont you experiment on an ice cream pail...
989#
Jason
or look at mine, it maintains water about 1.5 inches loher than the swing arm.
Jasom