where to get Mustang front end

Is it just the fender or are you looking for a grill, wings, and hood?

Have you tried your local car breakers/salvage yards?
If you truly live in Missouri there is probably a scrapyard with a Mustang with the stuff you need.

Ebay is good. Craigslist is also very good. Start with the junkyards though. They'll hopefully have what you need, and you won't have to worry with shipping.

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