I went out and tested the
Marco Polo mounted on the battery as in the image below it does not affect the GPS in an way 17 satellites before and after. The curvature of the plastic housing almost matched that of the battery. The only modification I made was to cut a notch on the antenna sleeve so I could aim the antenna up away from the drones body. With the housing it is also fairly water resistant although not waterproof (don't want to test to find out).
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