I hath opened the Great Book of Spitfires, and thusly having searched it's great texts forthwith, I find said book strangely silent on the subject of seats and interior color.
At least flipping through the pages over a cup of coffee.... I'm only up to the Mk. I in reading it.... it's HUGE!
I did notice that in all the diagrams of the interior, basically right up through the very last of the line (Spiteful), all the seats appeared the same as the Bakelite seat used throughout the life of the Spitfire Marks.
Didn't find any mention of the color, but everything I've ever seen indicated the brownish-red color, though on some early aircraft, they tried to paint it Int. Green but the paint did not stick.
Interestingly, the place it does mention Bakelite is in a few pages discussing experiemnts with making composite components for the Spitfire. Tests were done with several similar plastic composites.
I recall reading somewhere on the web- seems like a build report somewhere- that later Seafire marks were painted a with a dark gray interior. I can't find anything one way or the other in the GBoS, and the only pics I have of the interiors of Spitfires/Seafires are Br. Int Green, though I can't find any of them for the 46.
Now having said all that I realize it doesn't confirm or deny a thing..... most vague, I am....
Maybe I should run for office.... or maybe not..... perhaps a study.....
Jon Bius
AgapeModels.com- Modeling with a Higher purpose
"For I know the plans I have for you," declares the Lord, "plans to prosper you and not to harm you, plans to give you hope and a future." ~ Jeremiah 29:11