I'm trying to window select some parts to isolate.  It seems I have to start my selection window corner clicking an empty space in the assembly, but that requires me to select far more parts than I want.  Is there a way to start the corner of a window selection while the pointer is pointing at a part?

If there is a method, it could also be useful in other areas, for one off the top of my head, in the measure command, clicking empty space deletes all the selections, it would also be helpful in that case as well.  Any Suggestions?