Well, that was a difficult thing to do. Not physically, that part was surprisingly easy--she cuts like butter with the right tool. It's just sort of tough emotionally to cut a hole in a perfectly good hull that you spent so much time trying to make perfectly smooth. But the good news is I got over the trama pretty quickly, and made a box for the rudder cassette to slip into. It runs from the bottom of the hull right up through the cockpit floor (which I also installed today) This box is water tight--at least it's supposed to be. But it shouldn't get much water in it any way as the waterline is pretty much even with the bottom of the hull at this point.