66 Dart station wagon vs 66 Valiant driveshaft

I am needing a driveshaft for the 66 Dart station wagon that I just got, but the wagons are hard to find. Isn't the driveshaft for the 66 Valiant the same as the Dart station wagon, since the Dart wagons are the same length as the Valiants? Has to have the slide in front yoke. Nothing before 66 will work, and I don't think that any thing after 66 will work, either. A 66 Dart driveshaft wont work, since it is too long. Who knows for sure about the length?
Oh, it is a slant six auto with a 7 1/4 rear, if that really matters.