The effects house proved vital in adding a working lighting scheme to the model, although it now uses LEDs rather than incandescent bulbs. But the museum's own team did the bulk of the work, including building a new deflector dish after the original was lost at some point before 1974. With this restoration, the glory of the original model has been restored, although that only serves to highlight the tortures that the 1701 (Refit) prop has suffered since 1979. If you're unfamiliar, this forum thread should bring you up to speed, but it's fair that at least the original series model got a happy ending.