I apologize if this is in the wrong area. A problem I frequently has to do with having multiple copies of a part in an assembly. One problem I have is when I open the part from the assembly to modify it, even if I open it in the orientation from the assembly, it is easy to lose track of of the face/side/edge/etc. that I intended to work on. Most of the time a part is shaped with features that this isn't a problem, but it happens frequently with symmetrical mounting plates or cross-members. Is there any easy way to mark up the parts where each face would be lettered or colored uniquely that could be easily hidden after final assembly? This would also be helpful with choosing the correct/best aspects of a part to mate. I was hoping there was something quick or easy to do since this is only a minor annoyance.