I've been told by many people that I have to buy special headers to fit GT40P which is why I decided to put them on sale. I got some shorty headers from the 5.0 HO ford engine out the pick a part for 50 bucks and they bolted right on no problem! NO clearance issues with the spark plugs or anything. What is all this talk about headers not fitting? Are you guys talking about aftermarket headers which I would have to buy anyways?