What manifolds work with a 5.7 in an A body

A member named Gdemon used some sort of factory manifolds, I think Jeep, the drivers cleared but the pass side he had to notch the frame around the manifold if I remember... try a search with his name, I think he posted pics way back when...

In my opinion though the proven Dyno gains with headers alone over the factory logs make the headers a no-brainer even with the stupid cost.

Joe