When I was an auto mechanic we had a guy that would drop his GT500KR off for service. It was a hard top though and we would keep it for a week or so and I was the guy that opened up the shop in the morning. We kept it inside at night and I got to pull it out everyday. Needless to say I had to take it for a spin around the block once in a while. That was one sweet ass car. I'm not sure if it's true or not but he said KR stood for "King of the Road". The GT500KR had the 428 w/2 4bbl's.