My boss is working with some flow simulation and I got stumped by his question regarding an easier way to "pick" faces for a selection.  Marquee select does not work in assemblies for faces - only components.  So, as far as I can tell, he is left with manual selection or selection with tangencies - which results in about the same work as he only wants the right or left half in this particular case.

Is there a way to save a selection, e.g. like Photoshop?  I am not a great image editor, but saving/editing a selection for later use would be useful for certain things...

Is this where an assembly envelope would play well?  (This is something that I have never used...)

Thanks