If you want a good looking easy to build Spitfire Mk IX, I suggest that you look at Hacker products example. I have one, it's a 70" span model with a glass fuselage and abachi covered foam wings with the most accurate tip thickness I have seen. My Spit is powered by a Laser 150 four stroke that is totally enclosed within the cowl. The cooling is solved with a hinged hatch just below the spinner, that I can close when the model is static judged. I have made a alu-plate that fits around the cylinder to guide the air to the outlet that is situated below the scale air intake. The outlet is also covered by a spring loaded hatch. I have also fitted my Spit with flaps ( not in the kit). The model tips the scales at 5,2 Kg. I had to put 200 grams of lead in the nose to get the right c of g ( 28% of the root cord). It flies like a dream, with the only problem being the landing. If I don't put her down slowly she gets all over the place due to the narrow landing gear. I include a picture of her.