Obviously the OE resto is'nt using anything like the coatings being discussed here... But on that note if you're going the painted route Eastwood is always a good choice for the coating...Holds up well and can be retouched any time the need arises....Get the brush-on and use a foam brush...That gives the best coverage...The spray works well but takes too much to be cost effective on a complete manifold/header job......

Have'nt used the VHT Nu-cast {cast iron} coating yet but have used plenty of the black in the past and it's a good product also...As with any manifold/header application the key is good prep...