The 409 did not become available till 1961. Even then, they only made 142 of them. The '62 was the first regular production year. Also 409's never came with 3-2 Carbs.
It sure sounds like you've got a 348. They were offered with 3-2's.
But the sure way to check to see what you have is by the Engine Code on the Front Pad. Look right at the bottom and front side of the passenger side Head for a flat area which is actually the Block for some Numbers and Letters.
Post them once located and we can tell you what you have.
-Parting Out over 75 '58 to '73 Full Size Chevy Cars-
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