DrScoles, that is definately the bestlooking powerbox I have seen! Where did you get that one?
You are right, the optical sensor has to see the prop, with a max distance of 12" if I remember correctly. My La-7/Moki 150 has the rpm sensor installed at the bottom of the cowling (round as the Corsair), so an easy install. On the Spitfire, I haven't given it much thought yet, but the intake would probably be a good position as you say. A scoop cover on the left side of the cowling will also hide the small rpm sensor. I have seen pictures of Spitfires with and without scoops, so scale look would be maintained.
Last edited by kimhey; 11-30-2014 at 03:42 AM.