I am very cautious about taking positions on interior color for Tiger tanks, restored museum relics are not always represent of the original schemes. That being said, I went with the Bovington information and references, because I believe it was a restoration effort that focused on accuracy.
Since you have painstakingly worried about the right shade of eifelbein, you might want to consider that everything below the sponson line in the fighting compartment should be panzer gray?
You can see what I mean here, from the radio operator position, final drives and associated running gear are gray. When you look at photos of maintenance personnel removing and replacing these components, they are clearly not the eifelbein color.
Now, don't take me wrong, I don't want to start a debate and have this thread degenerate into controversy. It is clear that no one is really sure. It's your kit, hundreds of these Academy Tigers have been done before, and every one of them has a different interior color scheme. There are museum pieces with the entire interior painted off white, so I guess "what ever floats your boat" is the way to go.
Thats what I did on my 1/25th scratchbuilt interior project...Have fun Cowboy!...Steve