I trimmed at the 3/4" line as well as the bottom of the brace according to the dimensions on the plans. (The part comes a bit bigger/deeper).
Lots of material there for the most aft mounting position. As you can see, the 1" lightning hole is much more aft than needed, hence why in retrospect I shouldn't have cut that hole.
Next, I need to trim the rudder pedals to help lighten them. This is fairly straight forward.