Nassau Blue (Like in the Bahama's) was the color of several GM products, and Vette comes to mind. Thing is, those Bonanza's always looked more blue that Nassau. Nassau Blue is GM paint code WA3364.
Also see Marina Blue (like Chevelle of the era) GM paint code WA3481. These two codes get mixed up on the internet.
Also, see Mopar Paint Code B5 which is a way blue blue.