when playing around with my car I mixed up Doupont alt#1 c7 that is only available in BC/CC. I converted it to single stage urethane and used PPG green epoxy as a sealer,the color match was very close.I then did some cut ins with the same alt#1 mix but in BC and over V-shade#4 sealer,the color as expected came out a little lighter and less chromatic.
factory cars were single stage enamel painted over that milky green/grey sealer plus all the other reasons you have so many alt.color recipe.what plant,what day,what year,paint vat empty or full?your car painted at the factory early after a run of red cars,blue,purple,pink,green,black...you get the idea.
Plus BC/CC looks different over SS but by todays standards you would probably not care for a SS enamel metalic paint job.