I decided to paint the NACA ducts. I do know that no one will see them, however I wanted them painted the same colour as the side skin The early aircraft have the rear NACA ducts,( later series aircraft do not have them ), which did not work very well. The rear NACA ducts I have installed are to block and cover the rear openings and will not be used as air vents. I can not understand why this build is taking longer than it should.( I think KSC knows why ). I will drill a 8mm hole in top of one of the forward ducts for the OAT ( Outside Air Temperature ) probe, which supplies temperature input to the avionics. NACA duct is also called a NACA scoop, which is a low drag air inlet, developed by National Advisory Committee for Aeronautics ( NACA ), now known as NASA.