Thanks Ryan and anubis512. Our designers are relatively new at this so I appreciate the help. He was manually adding "restraints" in Cadworx that mirrored what was modeled structurally to create a simple support. What we found is that the +Y and guide supports work but the -Y did not. When he modeled in a restraint in the negative vertical direction it came in as another +Y.
I'm also wondering if anyone has done a sensitivity analysis on modeling clamps as a single Y with a guide vs. splitting the element up and adding a restraint on either end of the clamp in order to restrain rotation. Maybe its not worth the effort to put in several restraints vs. one. For some context we are modeling a ~250' diameter API 650 tank with up to 30" fill and suction lines so modeling stress accurately is critical. Thanks again for your help.