1967 340

looking at your link to small block I.D. I found a mistake in the first page, The engine number interpretation 3782 is actually the julian date code, not the days of production,
3782 = Dec 5 1971.
So your 2058 = March 17 1967

I don't think the #'s on the front of the block are correct, I believe march is to early for the block and I have never seen a 340 block cast before June of 67