Picked up a 72 Dart, stopping in for advice/ideas!

Welcome aboard! Very cool car. Vinyl top means there's likely rust under it, as Chrysler did not prep the roofs of cars that got vinyl tops very well. Places to look and "feel" for rust is all along the perimeters of the windshield and rear glass, and also on the sail panels down low going into the tops of the quarters. There's a factory seam on each side there and the factory just slobbed body filler in to fill the gap pretty haphazardly. I have seen a few that were solid, but most need help "somewhere" under the vinyl. Neat car, though. Is it a 318 or slant 6?