69 Dodge Dart Cummins Build
There is a 6bt in dart on the Moparts forum. But, he had to cut the fire wall out and it is more of a drag car.
I would go with a 4bt. If fits a lot better and weights as much as a iron headed hemi. The 6bt weights over 900 pounds. I have pics of mine that I'm doing now with a 4bt in a 72 dart.