Fixed the rudder alignment problem in what seems to be a very unorthodox way, but it works. Here's what they looked like when the boat was reassembled. When lowered, the starboard rudder was toed in about 1 1/2" when the port side was straight. And no, the upper castings and tubes weren't on the wrong sides. Also can't see any bend in the tubes - when held back to back with tube bends directed away from each other, the bends are identical and the ends of the tubes are equidistant from an imaginary center line running between them.
Took about an inch off the tiller crossbar which brought the rudders into alignment with about 1/8" toe in. The one thing I noticed when sailing after this fix is that tacking is easier without the extra (severe) drag. Even though the crossbar is shorter on one side of the tiller extension by an inch, I can't notice it when sailing.
Any guesses as to why the rudders got so out of whack?