Since it's purely a one-off, Carnut, don't you think that it would be more proper to identify it otherwise than "A 1955 Cougar"? Especially as they're have been other Cougars in that period (and in Autopuzzles too).
Maybe "Edwin F. Hasley Cougar" from its first owner.
Still, it would be fun if the answers to its present owner's questions were to be found on Autopuzzles.
“I was six years old when my uncle bought the car and brought it to the shop that he and my father owned. It always sat in the back of the shop, and moved to their new location in the early 1960s. My uncle had many projects but never completed them all and was a “saver”, so when I sold the car I put anything that might go with it in it.” “Over the years I was told two different stories about the car. The first story is that the car came from the Kaiser Design lab and was built by someone who knew my uncle. The second story is that the car came from the Kaiser Design lab where it was built for my uncle.”
"My desire and goal is to try and identify the designer(s) of the car, determine the intended vision of it so that it may be completed as such, and provide recognition for those who started it."