Defining Mass of Remote Masses

I have a main body and 5 small spherical volumes surrounding it.  I have them being treated as remote masses.  How can I define the mass of each remote mass?

Or do I need to enter them as forces and apply them in the Z coordinate?  I was hoping I could just enter the mass and it would take into account that I have a gravity load applied to the entire model.

SolidworksSimulation