68 RS Camaro Rocker Panel Black
 

I have to repaint the rocker panel area on my 68 RS Camaro. I would like to get the gloss on the black just right. The painter likes working with Dupont. Is there a formula or something to give the supplier to have the right finish. And should the gloss for rocker area match the black on the tail of a 396 in 68? I also plan to have the painter use a 1 stage finish in these ares, not a base/clear. Thanks