Help with H125 painting in Blender Please

I purchased the H125 yesterday and am impressed - thanks for a great rotorcraft!! One problem though, with the paint kit - when I try to paint the main fuselage in Blender, I get unwanted artifacts all over the aircraft, and it is VERY slow, even when painting without mirroring. Can you suggest a solution which permits me to paint the single fuselage file rather than having to paint each of the hundreds of components of the fuselage individually? Many thanks.