CAD Finder and Cleaner by Codigem is an excellent tool that helps in finding and deleting CAD Imports (.dwg, .dxf, .dgn, .sat, .stl, .obj, .skp, and .3dm) in the model and checking families. 

Functionality:

• Find CAD links/imports .dwg, .dxf, .dgn, .sat, .stl, .obj, .skp, and .3dm in the model (including groups) and families (including nested).
• Export findings result in .csv format.
• Delete CAD links/imports from the model.
• Easy filtering and navigation to the View containing view-specific CAD import/link.

Benefits:

• Find & delete CAD imports in the Autodesk® Revit® model.