The imperial form of measuremet was used and developed over millenia (Egyptians, Romans, Britons, etc) and we introduced it when we re-populated America, so the premise that the FAA claim we solely use metric is utter tosh. Ask your regular FAA inspector about Whitworth or BA measuring too....
A collegue of mine holds both FAA and EASA pt 66 licences. He got the EASA first, then did a short (a few weeks) course followed by an OPEN BOOK exam. This allowed him to gain the FAA equivalent licence. In comparison, IF he had the FAA licence and wanted to convert to EASA or CASA, he'd have had to do EVERY module.
edit: how the hell did we get here from ADD-ing valve caps?
edit 2: The A300 is measured in cm (ie. station numbers) but I can't remember if the fittings are imperial or not....