Joining Sloppy 2D AutoCAD Lines

Joining Sloppy 2D AutoCAD Lines. To Extrude a shape into a 3D Solid you first need to make a Closed Polyline. What if the linework has gaps and crosses, redundant or extra lines or arcs, or lines that aren't even on the X-Y plane? This shows how to use Flatten, Overkill, and Pedit>Multiple>Join to fix the sloppy CAD work.