Question on Dauntless

I was wondering if anyone ran into this.

On the Hasegawa 1:48 Dauntless. I have removed the plastic airbrakes, right, left and center and will be replacing with aftermarket photoetched brakes. I have painted the inner surface red and am waiting til tonite to paint the upper and lower surfaces.

Questions:

1) When I cut out the right left ad center airbrakes from the plastic frame, there is a pretty big gap. Should I fill it or should I just place the photoetched pieces in the center? It is weird. The other question is whether to separate the two flaps or leave them together, just bend them, upper and lower.

2) The center flap is only a bottom piece. The upper surface is still attached to the fuselage. What color is the interior of this? Is it also red or is it chromate green like the interior of the plane or is it white like the undersurface of the plane itself?

Unless you have done this model, this may not make sense.