Given that I built in my apartment, I went with this method because I could construct the beam with hand tools. Step 1) get (2) 2x4's -- Step 2) glue and nail them together. Going with Nick's internal strongback would have required bigger power tools. I actually think I would prefer Nick's method, though, because all the forms are kept together throughout the entire building process.

In this picture I'm aligning the forms. The front one is actually #2, and there is a bow form that gets mounted to it (it also has the teeny form #1 on it.) A ruler and level are used to make each form plumb, and the rocker of each form is measured downward off of the string, which just touches the center forms at the keel.

You strip the hull, then unscrew the forms from their bases. The hull is rigid at this point, so the strongback isn't necessary. The forms are still held to the hull strips by the staples, but they are no longer connected to each other. You then flip the boat roght-side-up into cradles and strip the deck. Then here's the fly in the ointment: once you pull the staples, the forms fall free, and you have to fair the boat without any internal support. It was a pain. Had I gone with the internal strongback, I would have still had a nice, solid foundation to plane/sand on.

Dean