Back in the day I used to use Centari. I think the color was called 99 Black. Its been a lot of years so I might be wrong about the number but I had to play chemist with a flattening agent. I could never get the same result twice. Too dull, too glossy. It was a pain in the butt. The first time I sprayed the support in the 81 I used a PPG black base with no clear. It looked nice but I didnt think it would hold up with no clear on top. I think some manufacturers make an "under hood" black but I dont really know what they were made for and what codes they would be.