Made up a doubler for the transponder antenna from .040 2024T3 and located it immediately behind the F-808 bulkhead. It is a great location for the antenna except that it covers up the drain location. If I had thought it through more I would have offset the antenna fron the centerline about an inch. I installed the doubler with 8 426 An3-3.5 rivts through the F824-1 skin. I fastened the forward doubler flange through the F-809-1 bulkhead.
Match drilling doubler to rivets in F-809-1 bulkhead