273 2v with EGR valve???

Rocky_JS said
it is cast in the side of the block (casting number)-273-x etc.

In 1965 the casting number did not have "273". That was later, and maybe only started with the 318. I have two 65 blocks.

The OP definitely needs to find what heads he has before buying an intake manifold since the bolt hole angles and size changed in 66+.