AutoCAD Inventor :: Change Color / Appearance Of Faces On Part File?

I quite often import hardware models downloaded form various mfg or supplier websites. McMaster Carr for example provides a great deal of hardware models.  While they offer native formats for SW they do not do this for IV (not many places do)

Since the [imported] models often open up with default properties, I change the material to something that closely represents the actual hardware or item.  In some cases, there are certain portions of the item that are in reality colored or textured differently and I sometimes want to duplicate that for aesthetics and a more accurate view for people that use my assembly files.

In SW, it was always real easy to select just a face (regardless of whether the surface was part of an entire part, a feature, an imported solid body, etc.  I could always change the properties of just a face or slection of faces.  Since it was a standard pc of hardware, I had no concern about updates.

I have a part file that contains two imported solid bodies.  If I select just a single face and try to change the color of it, it changes the entire part.  Not what I want.