I guess I'm pretty bored so here's an update. It's amazing how much work goes into these simple little pieces. Anyway this is the start of my rudder project. That is a piece of poly plumbing pipe with cedar strips glassed to it. It fits neatly into the extreme rear +-5" of the boat. It (gudgeon?) will live behind the miniature bulkhead (rear). The dark piece is a Walnut dowel with a steering arm on it and an additional piece mortised into the end; it's still fairly rough. It (pintle?) will pass through a 5/8" hole in the deck and into the pipe. I'll have the dowel pinned through a slot (not cut yet) in the plumbing pipe so it can be removed/won't drop out in a capsize. Probably a small spring pin - it's very tight back there.

If I can get this mechanism rigid enough then, eventually, I may mount a small electric motor the same way.