I have the same inclination with the interior of my 54, which is the original 2 tone deluxe blue. It is worn through use, faded and has a beautiful patina that just can't be duplicated. I dont think I will ever change the interior for these reasons. Maybe that is the same reason you leave the outside of yours alone.
Some photos:
https://www.dropbox.com/sh/ulj1ebjaygn644t/NbddmxexRY?m