67 Dodge Dart GT

More on the C body...if you can find a local re-spliner (ask at a dragstrip or machine shop) there is enough material on the stock C body shafts to cut and re-spline.

I have a friend who's nephew invested in the equipment and only charges about $50 to do it.

A 66-67 B body 8 3/4 is narrower than any other and might fit (they fit just fine in Dusters and 67-69 Barracudas), but clearance to the fenders will be tight on a Dart.