We're in business with the router jig for the centerboard!
This is what I have learned in the process (some of this is a repeat):
1. Build the jig with flat pieces that will accept clamps.
2. Build it out of a material that will not flex too much while you're using the router.
3. Width of the jig is important, having it too wide can cause the router to slip, and potentially gouge too much wood.
4. The bottom of the jig can be any shape, but make sure it is tall enough and wide enough to allow the centerboard to clear the jig.
5. Be conscious of the height of the router bit- you may need a router template guide (thanks, Joel, for the suggestion!) so you're not eating away at your jig.
6. Don't route all the way across, you'll need the edges of the centerboard to be square so you can clamp them together when you epoxy the two halves of your board together.
So, with that said, let me show you a preview of what the cross section of the centerboard will look like.
I traced the shape and compared it with the boat plans, and it's very, very close. I think this will work just fine!