Is there a plugin for this?

[pyroluna]

does anyone happen to know of a plugin that deletes all hidden components, groups and geometry except hidden lines that define non-hidden faces?

[Dave R]

You could use ThomThom's Clean Up tools.

See here.

[thomthom]

Yup, CleanUp will do that. I doesn't erase any hidden geometry that define visible faces, as well as edges defining the cut-out shape of a cut-out component.