OBJ to SketchUp Conversion

I have an existing 3D model in OBJ format that I’d like rebuilt natively in SketchUp (.skp). The OBJ came through as one big, solid block; before I send it to the slicer I need the interior cleared out so the part is hollow instead of fully filled... (Budget: €30 - €250 EUR, Jobs: 3D CAD, 3D Design, 3D Modelling, 3D Printing, 3D Rendering, CAD/CAM, SketchUp, Solidworks)