my first mopar, will i love it or hate it?

Welcome, and cool Duster! For a bb, you will need a 727 trans with the bb bolt pattern on the bellhousing. Schumachers makes engine swap mounts to basically bolt one right in. A bigger radiator would be a plus, and the more cast iron parts that you can swap out for aluminum parts, the better the f/r weight ratio (water pump, housing, intake, etc). Looking forward to more pics!