I believe what they are referring to, is that there were only 20 Fastbacks models built in the 1966 HCS. I've only seen photographs of two, this one and another in Columbine Blue. There is a photo of one when the cars were delivered at the Denver Rail Yard in 1966. The photo is in black and white, so I'm not sure if one of these cars is in that photo. Bob Teets has two in his registry, and I believe this car is not currently in the registry, which would make a total of 3 known to exist.