I recently made a Vertical Lift Rudder and Rudder Box for my Sonata 6.7 "Mark 2".The Rudder was a carbon copy of a friends Castle 650, no deeper in the water then the standard Sonata Rudder.
After installation the Sonata had excessive Weather Helm, packing out the Top Pintle did little to improve the problem.
On a recent visit to Canberra (family) and of course a visit to the Canberra yacht Club some Trailer Sailer acquaintances put me straight.
Remove the packing from the Top Pintle, in place, extend the Top Pintle, thus the Hinge Point stays as normal, but rakes the Rudder forward at the base.
This worked for the Sonata, look how it went in the last 2 races 7 & 8 (2017).