Thanks again for your help and your great plans. My Clark Fork Drifter is finished and working great! Here is a photo of it on the upper Mississippi. The project went great. Some rookie mistakes, but otherwise really smooth. I built the heavier version, with 6mm sides and 9mm bottom and taped both the inside and outside of the joints. I also expanded the plans 8.3% in order to make the boat a little more spacious, since I knew I would routinely have three of us in the boat. (I'm the only one among my fishing buddies with a drifter... suddenly those two spots for each trip are in demand!) It got heavier, but feels great in the water despite that.
I couldn't be happier with the ease it rows and the balance of the hull.
Thanks for a great set of plans, and for being available when I had questions. I really appreciate it. Can't wait to figure out my next project. That Freight Canoe of yours looks great...