CAROLINA BLUE PAINT CODE?????

[kodi396]

I have been searching for information on the paint code on my 68 Chevelle SS396 convertible. It was built in Baltimore and sold in NC. The paint code on the trim tag shows 2393-2 where the paint code should show a letter. It has a black top as it should. I know I am reading the tag correctly. Could someone please try and shed some light on this code. I have searched unsuccessfully for a build sheet. I found a small area of original paint (car was redone in the 90's) and it is a sky blue called Carolina Blue, available only in North and South Carolina. Please help!!!