Oh if only you knew the pains I go through trying to figure out good antenna placement. If it helps any, (and I have to chuckle) My son still has his "Fun 51" from years ago. We both bought the kit and assembled them using different schemes. Talk about a hoot. Them buggers haul the mail with just the right sized motor. Anyway, I really don't remember where I placed my receiver antenna. Heck, it has been too long ago. His on the other hand.... (chuckle) is stuffed inside the wing hatch, "UNDER" the battery with a servo lead going right across the top of it. Not a single glitch. Says something for the Hitec rec's. LOL. If it is any assistance, (and I would assume all radio manufacturers are the same) They say keep the antenna end at least 1" from any other power source, i.e., ignitions, battery, servo.... You know? Dual Boda should be placed 90 degrees from each other. (You knew this, but just tossing it at ya) As for carbon? I have been told to keep the antenna/s as far from it as possible. From what I have been told, carbon is basically a blocker. Creating a shadowed effect. I dug this up from a google search. Maybe there is something in the midst of these pages that will offer some assistance? Good luck buddy.
https://www.google.com/search?ei=vS.........0i71j35i304i39j33i299j33i10.jzbR9xr6FrY