I did a little research on the GTM exterior once, there is an incredible amount of personal customization going on (most of it very nice, but not always to my personal taste).
I can only imagine that the interiors of the GTM cars are just as varied and customized, at least from a finishes viewpoint.
My point, if you love or hate something like a Solstice interior, most likely if determined to do so, a custom interior seems possible.
olpro, as I've mentioned before I like to compare different vehicle egonomics, their functions may differ but people are people and they still have to fit. One of the most popular light aircraft with side by seating is worth looking at, just for a back of the mind reference, at least I think so.
Cirrus SR22
http://www.classg.com/aircraft-perfo...SR22-specs/547
The Cirrus SR-20/22
http://www.airliners.net/aircraft-da...ts.main?id=167
Cirrus SR22
http://www.the-blueprints.com/bluepr...w/cirrus_sr22/
Attachment 5255
Cirrus SR22 Aircraft Seat Covers ..........
INTERIOR PHOTOS
http://www.aerosheep.com/Cirrus/SR22...at-covers.html
http://www.flickr.com/photos/observe...413983/detail/
Attachment 5256
I have not been in a Cirrus SR22, but my cousin (a pilot) has and tells me it's very nice. From a design standpoint, I like the whole co-pilot concept for the passenger, so they do not feel less important than the driver. However, in the end it just has to make sense otherwise it's a square peg in a round hole.