Frank, there was a reason for the Light Gull Gray rudder on your Demon that you did for the FSM article.
A photo of your aircraft taken in 1963 shows a White rudder, and a photo of the same BuNo taken in 1960 shows the Gray rudder, as you built.
The reason that aircraft had a Light Gull Gray rudder in 1960 was that the spec to paint the rudders White didn't appear until a change on 12/27/1961, before that, the rudders were painted Gray from 1955 on up.
As we know, the specs didn't mean that the colors changed instantly, but, it was very rare for the colors to change before the spec came out to change them. (it could have in other instances, when the "usage drove the specs to change", but, this wasn't one of those times)
I just thought you would like to know, and erase an "unknown" for you
Rex