I know this won't help answer your question, but I had a 427 tunnel port back in the late 60s and I kept some of the papers on it where I had written down numbers. I have the same SK number written down as shown in the picture but I have no clue as to who built the heads as the engine was built back East by an outfit that has long been out of business. And mine and the block were cast iron, not aluminum. Only the intake was aluminum. About the only thing I remember was when I sold it to a drag racer, he pulled the cam and said it looked like a stick with footballs mounted every few inches.
Ron
