I have been developing a multi-body part and had successfully assigned different materials to each body.  (I'm using a mix of metals, wood, and acrylic).  At this point they are appearing as "cut list" items.  I took that part and did "save as" to use as a starting point for a different, but similar "part".  I seem to have lost the ability to edit material by body as I had previously (right click on body in feature tree)

Is there a way to get this function back?

I am using 2016 SP3.0