Hi all,
Re "Moore Girl" as sung by Willie McTell and spoken by Jim Baxter vs. "mogul", the actual name of the engine type in question, it occurs to me it may be neither a pun, nor a deliberate mishearing, but a cultural way of coming to terms with, and making sense of a name that bore no connotations that made any sense. I once read a brilliant essay by the late writer Walker Percy (who was from Mississippi), called "Metaphor As Mistake". One example he gave in the essay was the fact that he discovered, upon visiting a juke joint, that everyone referred to the jukebox as a "seabird". Come to find out, the jukeboxes were manufactured by the Seeburg Company. I think the name "Moore Girl" for "mogul" came about via a similarly circuitous route, making sense out of something that otherwise didn't make sense.
All best,
Johnm