I say change whatever you feel. I figure there's enough correct restoration cars out there to last forever. Take a non numbers car and have fun with it. When I get mine, I plan on doing some custom work, especially on the interior. I feel the exterior of an Ebody holds up fairly well (though shaving markers and handles could help smoothe them out), but I always hated the interior look of the cars. Seats with heavy bolsters, custom console, navigation. It would be awesome.