Tim, it was originally yellow. The engine came from a '57 6400 cement truck. Everything but the block had the original yellow paint under several layers of Chevy orange. The block was replaced at some point in its life. It has a 1964 build date and no serial number. From the research I did, '57 was the one year the 261's were painted yellow. Since it started life yellow in a '57, and since it is going into a '57, I painted it yellow.

Thanks for the comment about the manifold. I got the ideal from this site--

http://www.restorodstogo.com/2011/01/235-261-chevrolet-split-dual-exhaust.html

HRL helped me with advice on welding cast iron and how to split the cylinder banks by milling a slot through the back side, then fitting and welding in a plug.

Matt