Select a 3D cube face that’s behind another face, without rotating the cube

I'm working on a software program that handles many 3D objects. Imagine for now that all objects are cube shaped and 100% transparent, only the edges are visible.

In the software program you can select only faces of objects. You can currently do that by clicking on the face that's aimed towards the user. When you hover over a face, it gets highlighted.

I want to make it easier for users to select a face that's behind another face for the same object. How can this be achieved in a clear and user friendly way without rotating the 3D object?

To illustrate:

In the above example, how can I easily select the 'bottom' face? Right now when you would hover over the 'bottom' face, the 'left' face gets highlighted.