I would like to use API calls to individually edit the definition of composite shells in a part with numerous surface bodies and varying properties. The GetShellAt() function takes an index to a shell in order to select it for further editing. It appears that shell indices are randomly assigned to surface bodies of my model. I have not found a way to use a selection function (such as SelectByID2, or GetSelectedObject6) to lead me to finding simulation study shell indices. This would be essential in order to assign for each shell the proper composite configuration (e.g., thickness, angle and material for each ply.)  Can anyone suggest a way to determine a shell index either by using the name of a SURFACEBODY or by user selection from the study tree or from the graphics area? Thanks!