It could be any color, really. (Well except the Cadillac FireMist colors that had to be shot with a special gun.)
Carolina blue could be ordered by any dealer and they would pick whatever shade they thought was good. I've heard of some groups of dealers using one common shade, while others dealers picked other shades.
Carolina blue was also a special order color in 70, not a factory color in 70 to my knowledge.
The only real way to tell the shade is to have the paint scanned and match the color. I know that a 64 Wedgewood blue was used on some.
Colorado blue was a very similiar color, btw.