When I built my Riv motor I used POR 20 manifold paint, you can brush it or spray it, I sprayed mine. Not sure what color your manilfold should be but I really like the color of this and it's been holding up very well so far.
I was kind of thinking the same thing, hope you have your fire suit on because you're going to get roasted for this :-D
That said, my experience is pretty much everything is crap no matter where you get it from :angry7: