1901 - Henry Ford founds the Henry Ford Company (soon to become Cadillac after Ford leaves to found Ford Motor Company) in Detroit.
Your challenge is to either have Ford start his auto-making career somewhere other than Detroit, or have someone else do the same, with the end result that a different city (perhaps one of
these) becomes the center of the American auto industry. I'll give you a cookie if you can make it Buffalo.
Have at it!
Added: Start of a possible TL. Anybody more familiar with Ford and auto history in general, feel free to tweak it!
1879 - Henry Ford moves to Buffalo, New York and works as an apprentice machinist at the George N. Pierce Company. He also begins to study bookkeeping at Bryant & Stratton College.
1900 - The Ford Automotive Company is established by Henry Ford and a handful of engineers and workers from Pierce. The investors include Buffalo businessman Seymour Knox I.
1901 - The Pan-American Expo is held in Buffalo and Ford's exhibit "Automobiles of the New Century" draws much attention, if being somewhat overshadowed by the assassination of President William McKinley.
1908 - FAC introduces the Model R (OTL Model T) and the first production model leaves the Abbott Road factory in Lackawanna.