England, Australia, New Zealand Info Requested

[Bruce Lancaster]

Something that interests me that I do not yet grasp: How did they juggle the 2 different meanings of "AF" and "BF" in English production? Seems to me from the little I have learned that those prefixes in England could designate either a car with US type 200.5 inch engine and RHD OR a small bore English engine? A small bore AF or BF engine built in England could quite conceivably have been built with LHD for export into the continent...