My 1st attempt at putting a stack on my 455 was not all that sucsessfull. My welding was far from good to many bends and vibration.
So I came up with plan B. As the hood has a chunk out of the corner and is not in the best of shape. I cut a hole in the hood directly above the manifold and run the stack throught hte hood. Painted it flat black with high temp paint.