USC do say they are licensing a Skoda design, as well as using some of Skoda's parts (40% is imported), so that would most likely be the reason. Even allowing for the mods made for the US, it would make sense to not try to convert to imperial - no gain, and potentially lots of pain, especially if metric part A didn't fit with (converted) part B.
Back in the very late 1950s/early 1960s, an Italian company Piaggio made (and still make) Vespa scooters. They started to be made under license in the UK, its biggest market. At first the drawings were converted to imperial, but it was found that minor conversion errors meant that some parts didn't fit properly, or that some tolerances became too big/too small. Once manufacture reverted back to the original metric drawings, the problems disappeared. Interesting that USC didn't mention that Skoda is part of Volkswagen. John F-L ----- Original Message ----- From: Carleton MacDonald To: U.S. Metric Association Sent: Sunday, January 17, 2010 10:52 PM Subject: [USMA:46426] Metric domestic streetcars Note the dimensions on the drawings, about 2 min 26 sec in. Carleton http://www.youtube.com/watch?v=QU1W9EOxBhE