Here's a tip to make your rudder modification go smoother and easier.
Go to the bottom of page two of the instructions
http://static.hobiecat.com/linked_images/kayak/TI-Retro-88991186.pdf . Take a close look at the picture of the completed job to determine where the bungee should exit your rudder housing. Take a small piece of tape or a posted note and stick it on the place the bungee will exit the housing BEFORE you pull your rudder pin.
Now, when the rudder pin is removed and you have the housing upside down and reversed in your hand you can use the tape to make sure your drilling in the right area.
I did not do this when I did my modification and got it right anyway but I spent a lot of time trying to figure out where to drill. The tape would have made the job a lot easier and faster.