I think Yunit is over in Jersey. You may want to ask him if he'd help... Or I am sure any body shop could do it....
As far as the interior goes... The seats and all should swap. The door panels are a little different on the older K5's, but they may swap also. The dash, however, is a slightly different style wiht the older one being shallower around the gauages than the newer ones. And the carpet will fit the front, but the older k5's had a different rear floor design and the newer carpet wont fit the older(<76) since the floor wells where the passengers feet go are different..