With the added small picture I must revise the spotting here .It has the 4 doors opening in the safe direction and no rear quarter windows making it a 1940 Buick Super 4 door touring sedan model 51 rather than a Buick Special.The Super used the same " Torpedo" body shell as the roadmaster but was built on a smaller chassis of 121 inch, the same wheelbase as the Specials.Morality : when you have good thumbnails try to add them immediately and not afterwards,they often help a lot.