N11FE is probably the #1 Warbird I'd love to own. Seeing as how Dick Foote (who was a Vought test pilot during the war) not only owned and operated this bird out of Connecticut for years, but he was also part of the "Warplanes International" team which performed a reenactment of the Pearl Harbor attack with a replica Zero and Kate as well. I grew up watching this video of the 1985 Pratt & Whitney Airshow ad nauseam.
http://youtube.com/watch?v=G2HCRVHdzTM (Skip to the 28:50 mark.)
I think this additional seat modification is not only unique, it's down right useful! And I'd hate to see it removed in a potential future restoration of this bird. With every other Wildcat out there in a stock configuration (more or less) you'd think this one would be highly sought after for its practicability. Also something interesting to note, I believe the nose bowl is actually from a Lockheed Loadstar and not a Wildcat. One of the other quirks this airframe has (that I honestly love).
Now... if I owned her, I would have her gone through extensively seeing as how she has some high time on her. I would want to preserve the paint scheme as is. Or if it was necessary to strip the airframe to inspect the skins, then replicate the scheme as close as possible. As for the interior... it's age is definitely showing, and I'd want to reupholster the interior to OD canvas and make it look as WWII period as possible to make it seem more authentic looking while keeping the extra seats for passengers.