In thinking about this for a while now, I think the simplest answer is going to be to come up with a rounded cover that allows for extra space having the junction box sit halfway in the cavity and stick up. As long as the junction box is under the cover, and the cover is smooth, there will be very little aero penalty.

All that has to happen is to design a new cover that allows for extra space underneath it rather than the relatively flat one that is there now. It would need to be about an inch taller and the designers would need to check ahead of time to make sure the junction box fits underneath it.

With this solution, there doesn’t need to be any real structural changes to the tri rig device itself.