RE: Aileron gap question.
No part of my Dave Brown spinner (from Tom ) extends aft beyond it's center. The backside is recessed some, but comparing the center and the outside edge, it is essentialy "flat". That being said, you're going to want your exact spinner in place to get the "look" of the thing the way you want it when you set up your engine mount. Mine is actually a litlle higher than center (1/16"?) to get the top cowl/spiner profile just the way I wanted.
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