Chevrolet did not badge the Corvette as a Stingray (one word versus the C2 Sting Ray) until 69 and ended it with the 76 model. 1977 was the last year for the vertical back glass. A friend of mine has a 68 and when parked next to my 69, mine said Stingray and his didn't even though they are pretty close to the same car (a lot of minor design changes, ie: door lock push buttons on the 68, back up lights in the lower valance on the 68 and incorporated into the inboard lights on the 69, no fiber optics system on the 68 etc...). So the answer to your question is there were no Stingrays built from 1978 to 2013. It is your car and your money, do what you want with it. No one is going to flog you for adding the emblems.