Honestly - you can cut the skin off the unibody, lay it over a tube chassis chromoly chassis, stick a glass nose on it and some aluminum tinwork, and get it down to 2500 or less race ready depending on the driveline. It would still be easily recognizable as a Duster. personally I don't like glass fenders I have to work over, fiberglass doors on a street car, or climbing over a bar to get in (back is getting tired). But replacing hardware, omitting non-essential parts everywhere, removing or "holing" bracing structure, etc, can get you hundreds of pounds looking bumper to bumper.
