List of GM factories, may not be perfect, it is Wikipedia afterall
“Ummm...the factories aren’t just in Michigan: they’re in Ohio, Indiana, New York, Missouri, Delaware, etc.”
I think that the use of the name “Detroit” when talking about any U.S. auto topic is more of using it as a identifying symbol than anything else. When you say Detroit, people automatically think cars. The right words for this escape me, so anyone help me if you can.