For sure, I would be interested, even maybe for a full shell, top and bottom.
Other RF issues, the top half of the shell really isn't load bearing or having cracking issues; it's really only serving as a top cover for the aircraft. So the bottom half is the only one needing replacement. This would keep the cost lower for the mod, while still realizing the benefits. But if someone wanted the top too, it would just cost more.
I'm not sure how much yet, but I'm looking into the feasibility of designing a bottom half, and the cost associated with it. I'm an engineer, and think this can be done fairly easily, cost is the only issue for the design part. After the design is done, I think repeatable 3D printed shells can be made for <$500. To me, I'd pay that amount for the peace of mind of a robust aircraft frame. Thoughts?
Based on what I've seen from tear apart postings for the P3 - a GPS/Glonass receiver chip/module is in the center mounted on the main PC board. The receiver would include an antenna that would be "RF signal blocked or attenuated by carbon fiber whereas the plastic is RF signal "transparent" or at least negligibly so.
That would be an awesome price for a CF shell if feasible. Someone estimated an object the size of the lower shell 3D printed would cost more than that though. I'm not sure that anything could drive it down except for mass production. Plastic in mass production is probably $5-10 for the part, so we see why DJI is using plastic.
