Wow! Thanks Bob - very good info. I'll go with 5/4 cedar. I'm thinking that the fairing may not be to bad - this boat was designed for plywood, and so I'm basically building straight flat hull walls - but I've been wrong before. The only thing I'm concerned about is using the 5200 as caulk - when it comes to fairing, 5200 doesn't come off - but from what you're saying, I could probably use something less adhesive - white lead, or caulking maybe.
Dale, I took a look at the Tom Cat - very humbling - they are doing an incredible job. I'll be happy if mine looks half that good when completed. Yeah, It will probably take a couple of years to complete, I try to work on it a full 3 minits at at time - then I need to spend time with the kids and wife. Just enough time to measure a board or take a clamp off. On the bright side, all the time between the 3min spurts, I can spend figuring out what to do next. :-)
Tom