http://rarevettes.com/sitebuildercon...car_74/001.jpg
So there were 1994 Brickyard convertibles with an NAO designation..
THERE ARE SEVERAL CLUES TO IDENTIFY A BRICKYARD 400 CORVETTE. ALL WERE CONVERTIBLES, EITHER RED WITH RED INTERIOR OR BLACK WITH BLACK INTERIOR WITH A BUILD DATE ON JUNE OF 1994. BUILD SHEETS OF MOST KNOW CARS HAVE A ?CHARGE-TO? CODE OF 00-502 {NAO CVO-TECH. CENTER} AND A? SHIP-TO? CODE OF 70-847 {C-P-C GROUP C/O QUAL-EFFIC INC.}. THE CARS ARE ALSO IDENTIFIABLE BY VIN THROUGH THE INDY MUSEUM HISTORIAN AS WELL AS BY THE COMPANY THAT SUPPLIED THE ORGINAL BRICKYARD GRAPHICS FOR THE CARS.
http://rarevettes.com/94byard.php