As far as I can tel, you have a 216 of a 1952 vintage.If you can locate the casting number we can verify that for sure.
I was thinking that it might have been a GMC engine from the earlier pics which did not show very much other than the color and the straight drop of the center of the manifold.

There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
-
-
Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!