So my question is, what does "installed in an FAA approved manner"
actually mean?
Do they really mean Field Approval, or are there other FAA approved
manners in which to go about this installation?

My take is this: If it can be easily removed from the plane, and it's not
hard-wired in, it's okay to do without FAA involvement.

How is the Air Gizmo panel mount any different from my yoke mount, in that
regard? Answer: It's not.

Let us know how it works for you.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"