In any event ...beautiful cars!

Yea, on inspection, you are right. The solid cover appears in 58-60. And, the sources for lenses call for the same lens for 56-57. I was no expert on this anyway, but I did have a 61 and I knew that call was not right on that as soon as I saw it. These were great cars. Too bad they are so expensive today. I had 5 Corvettes and wish I had every one of them back today. They would make a nice collection.