Doug Thorley Headers with SB Trick Flow Heads

I know this may not help, but I had Dougs on my 65 360 Valiant. I had Schumacher /6 to small block mounts with a 904. They were single handedly the easiest headers I have ever installed.....on anything. All I did was follow the deestruckshuns step by step....yeah, you have to remove some stuff, but for it to have been any easier, they wouldda had to install themselves. I even kept the slant six center link because the pan didn't hit it. It was close, but it never hit. I didn't have to dent one single tube anywhere.

I say all this because your story here makes me thing you have a mount issue.....maybe wrong ones, or maybe installed on the wrong side of the mount ears. Don't laugh too hard. I've done it myself. lol