What am I looking at?

That's kind of what I was thinking too but I couldn't say for sure. I've got no idea where the manifold is from, the engine is a 1975 but the original thermoquad on there was later so it could be the case. I've got a Holley and been using a carb adapter too, I think I'll probably just pony up for a new manifold at this point.

So now the question is, LD340, performer, or air-gap?