[Jeff H]

Strange looking intake. I don't see the heater hose connection. And the winter's snowflake looks like it might be a prototype manifold or very early production whatever it was intended for. Are there any dates on the exhaust manifolds?

 

[Jeff H]

I'm guessing that's a marine intake if it has brass fittings. The exhaust manifolds should have dates cast into the back side of them(side facing the engine).