My guess is related to the fact that the early Model Ts had no driver-side door, supposedly because Henry didn’t want drivers stepping into the street, believing that the curb side was safer. Putting the wheel on the left allowed the passenger to enter without having to climb over the driver. This is a pure guess, not based on any documentary evidence and without research. It may be that the single door simplified the production process, allowing cars to be built more quickly and at a lower cost.
Henry later added the driver-side door to the T. Some may say it was to try to modernize Lizzy as sales and market share slumped. Others may say it was because he was so fed up with stupid consumers and their stupid “preferences” that he wanted the most foolish of them to step out into traffic. Hard to say.
P.S. Synchro - So when the wheel was moved to the starboard side was the engine rotation, along with the starter, oil pump, generator, and distributor reworked to rotate the other way?If so, it’s no wonder Australian parts are so hard to find.