'57 DeSoto Adventurer Convertible, 345ci 2x4 Hemi
 

From what I could find from a cursory search, this car is one of 300 convertibles built with the 2x4 345ci Hemi mill. Super cool car. That said, I can think of other ways to spend $300k...but to be fair, I'm thinking a proper restoration of one of these cars would likely cost a good chunk of that asking price.

Link to 1957 DeSoto Adventurer Convertible auction

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