Bob,
Beautiful little bugger, and not half bad considering her age, especially in regard to the interior. In regard to what needs to be replaced, the main thing you need to consider is whether or not you want to operate the car. If it is static, you can retain much of the original material, though it will be coated in putty and epoxy. If it is to return to service, replace anything on the exterior that is rotten, but try and maintain the more difficult details, such as corner posts and roof arches. The interior should be able to easily be repaired and maintained with the majority staying original. The framing and such can be surprisingly preserved even in such a weather worn car, but of course, don't be surprised if a major structural issue flares up. Anyway, the car is a great survivor, and if it were up to me, go for an operable restoration......then bring it up to the Sumpter Valley for a visit.
Thanks, Taylor