After being involved in some restorations, I figured out that premium prices paid for relatively rust free sheetmetal and bodies that need less work is a good investment. Not getting any easier to find, at any price. I would think the project you are suggesting would be major and probably need donor parts from a hardtop car that could have been redone itself.

While on the subject of Darts, anyone ever use a 70 & up hardtop Dart shell, that needs quarters anyway, to build a '68/'69 Dart?