finding a 67 Dart steering shaft

An A-body friend of mine passed away unexpectedly a few years ago. His widow wants to drive his 67 Dart to local shows and such, but he had manual steering on it and she can't handle that very well. We located a whole power steering set up for her, but what she doesn't have is the shorter shaft for the steering column. Can anybody describe how to identify a 67-69 shaft (as opposed to earlier or later), and does anybody know how long a 67 power steering shaft is?

Thanks for any help you can offer!!!