One last thing - are you using the font "AmarilloUSAF" for the ID letters on the tail and fuselage? I can't tell from the screenshots but the "H" on the inside tail looks slightly thicker than I imagine AmailloUSAF to be.
The font is available from skinner's heaven.
Kev367th has a layer that contains all the warning texts blocks that appear all of the aircraft, if you're interested. Adds a bit of authenticity even though the text is unreadable for the most part.
Oh, and on the outside of the nacelles, down near the front-bottom, there is a panel called the "oil radiator shutter", to which a shadow can be applied along the top and front lines to show the shutter is open. Its a square panel directly aft of the oil radiator intakes under the prop spinners.
Its looking very nice!