Decided to mount the com antennas under the passenger seats next to each other. This gives me access to the base of the antenna inside the cabin and provides over 36" separation between the two. Created a couple of backing plates to provide extra support for the antennas between the ribs. Cut the holes to mount the antennas. Added nutplates to the backing plates to make installation and removal easy. Assured that the antennas were parallel. Also mounted the transponder antenna on the copilot side just in front of the pedals. I chose this spot based on a survey of vansairforce readings.
