Chine Spray Rails
First; it looks like the rail was not fitted according to plan🤔
However; my Sea Scout has no rails at all (Yet!) and as you have seen in your other thread on this topic she runs fine with the same profile rudder.
BUT; I notice that your rudder extends well below the prop. Mine only to about half way down the lower blade and she's very responsive with no sign of digging in.
Before messing up a nice hull I would trim the rudder back to at least the lowest extremity of the prop. Do another sea trial and if she still digs in a bit lop a bit more off, to about half way down the lower prop blade. 😲
Easier to mess with the rudder than with the hull 😉
Cheers, Doug 😎