If God made man in His image, then I think we can assume that God is man shaped. Jesus had to be standing to the right of something. That God was seen as standing separate from Jesus in the vision should be convincing enough, no matter what shape he took.<quoted text>
There are 3 personages, one being. Stephen saw Jesus standing to the right of the Father's glory. He doesn't say that glory was man shaped.
If Stephen saw them distinctly, then I think its safe to assume that they are distinct or separate beings.