The Phoenix hasn't run right since I last did any serious work on it back in January. This last weekend, though, I popped the hood and went back to work on it. The new thermostat (along with the correct gasket) went in like butter — the 15-minute job it was supposed to be. I found where the extraneous vacuum hose went. It started! It took a while to clear out the old gas out of the carbs, but once that was done, it ran just fine.
Granted, the right-side door still doesn't work. I improvised with a few bungie cords for the test cruise, but that kept opening a few inches when I went around corners. I admit my first instinct was to just tack-weld the door shut, but I'm not sure that's the best way to go about this.