Hey highwing, how does the hinge work on your aluminum trim tab on page 4. Is the one picture (with it uncovered) showing the servo and tab installed in full down position? It would seem you would have very little or now down and a lot of up movement available do to the hinge being fully closed. Did you mount your square hinge attach bar rotated slightly down to get some down movement? Also is this the hinge that is used in this.
The aluminum tab used was formed to the shape pictured. This gives a profile that allows for the full range of motion of the servo - up and down. Regarding the hinge. What I used is not the hinge in the link. I did find the description of what I used lower on the page -
MS20001P aluminum hinge is extruded. The closed hinge loops cannot be pulled apart. Furnished with hinge pin. Anodized finish.
But or some reason, I couldn't find it as an order item.