Not sure how these engine paint formulations can get so screwed up. For decades Oldsmobile metallic blue from the early 70's was dead on for the '75- early 77 Pontiac blue. Was available locally at NAPA. Used quite a few cans.
Many years ago I picked up a a small can of metallic blue that was a near dead on mix for the '75- early 77 Pontiac engine paint, & it was labeled "Hawaiian Blue"
On the commonly referred to reference page on Pontiac engine paints through the years, now hosted on
www.Pontiacpower.org , the color of "Corporate Blue" at least on my IPad is waaaay off. If nothing is dead on out of a rattle can for Corporate Blue, just will have to have it mixed. That was the only solution when I first had '71-early '73 Pontiac blue made in the late 80's & offered it for sale.