Changing the pose of an included model via plugin

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In my world file I have:

<model name='gimbal'>
      <pose>0 0 6 0 0 0</pose>
      <static>true</static>
      <include>
        <uri>model://gimbal_mount</uri>
        <pose>0 0 0 0 0 1.57</pose>
      </include>
      <plugin name="GimbalModel"
                    filename="libGimbalModel.so">
      </plugin>
   </model>

in GimbalModel plugin I wrote I would like to change the pose values listed in the include gimbal_mount portion, i.e. change the 1.57 rotation dynamically in the code. I can't seem to figure out how to access and change that pose. The model->WorldPose is adjusting the pose (0,0,6,0,0,0) which I don't want to change. Is it possible to dynamically change the gimbal_mount pose in this model?