Darts and Dusters appear to have similar underhood bracing. At least many of the extra holes are in the same place. If your scoop comes with studs already installed, they "should" line up with holes in the bracing along the centerline of the hood underside. But double-check the measurements because the framework and/or holes can be off by just a little bit. Once you get the first two holes located and drilled, the rest are easy to mark and drill. Some frame holes may require trimming if the stud is off center so you can get a socket in there.

There were also 2 scoop part #'s because the Demon hood was mostly flat while the Dart Sport had a little peak. Depending what scoop you have will determine how well it fits/follows the flatter Duster hood.

No Dusters ever had that scoop as an option from the factory. Only '72 Demon, '73 Dart Sport and I'm not sure about '74 Dart Sport. I even got a hood/scoop assembly off of an original '73 318 Dart Sport, so it didn't have to be a 340 car.