How do I paint the black on the inside of the windows?
The best result will be achieved by spraying semi-gloss black paint over Tamiya masking tape or the masking set included with many models. Apply the mask to the clean clear plastic, rubbing the edges will with the back of a fingernail or something similar. Then apply a very light dust of spray over the area, and leave to touch dry which is about 5 minutes. This seals the tape edges against paint ingress. Then apply another slightly heavier coat, allow to dry, and then another, until the surface opacity has gone. Remove the masking tape within 30 minutes to prevent the paint lifting with the tape.