
The first thing I did here was to install the rudder backing plates (plywood strip in the drawing). But, because I changed the design of the rudder mounting (more on that later), mine don't look like the drawing. They look like this:

Next I glued in the keel fin. The slot in the hull that the keel goes through is a little wider than the keel is thick, so there are two little slots on each side of the keel. The fin has some wood strips on it that are supposed to seal this area, but I found that I just hadn't made things accurate enough to get a good seal. I wasn't thrilled with the appearance either. Off I went to my local hobby store where I bought some "liquid plastic". It comes in a tube and works like wood filler. If you've ever used this stuff you know that the working time is very short. The liquid plastic I used can be squished around for about a minute before it starts to become clumpy and half dry. It's a pain, but after three applications and sanding and forming, I got a satisfactory result both in sealing the opening and an adequate appearance of the hull keel joint. It ended up looking like this:

Right after finishing the hull - keel joint, I painted the hulls. Masked off a strip about a quarter inch wide all around top edge so the deck would have something to glue to. I was still concerned about the hull keel joint leaking, so just to make sure, I slobbered RTV all over the joint on the inside of the hull.

You'll notice in the photo above the lead weight just in front of the keel fin former. I glued this and anything else inside the hull in before the deck went on.. The instructions have you doing some of this later through the hatch, but I couldn't see any good reason not to do it before the deck went on. Now is also a good time to think about installing some flotation - the assembly manual mentions it not at all. I decided I would wait until the boat was finished and then just fill up any empty areas with foam peanuts. Would have been easier to do it before the deck went on.
Even though the photo above shows the deck on, pretend it isn't. I just didn't take that picture.