On Tuesday, May 8, 2018 at 10:06:56 PM UTC-7, Wade G wrote:
In short,
What is required to install a non-TSO’d moving map flight computer IN the panel of my certified glider?
A 337 mess?

WG

I would think not. If it is not a primary flight instrument, and I assume that you are keeping all of those, it falls into the category of an accessory. Sort of like in flight music. But, by all means, call your local FSDO for clarification. And, if you make the request in writing, the FAA will give you a formal determination. This may be a good idea before going to all the trouble and then having some uninformed mechanic say he can't sign off on your annual because of this unallowed mod.

Tom