Using xpctag with SimMechanics sensors

I have a SimMechanics 2G joint that is outputting its position using the built in sensor. I will be generating code from this model and running it real-time on a speedgoat target computer. I would like to take the joint position signal from the target while running and feed it back to another simulink model to drive a visualization on the host computer.

I am tagging the output signal of the PS-Simulink with xpctag as described here: http://www.mathworks.com/help/xpc/ug/xpc-target-interface-blocks-to-simulink-models.html?searchHighlight=xPCTag%28#f4-27459

However when running the SimulinkRealTime.utils.createInstrumentationModel function on the model it gives me a warning saying that I can only mark the output ports of non-virtual blocks.

Is there a workaround for this in order to get the SimMechanics sensor signals from the real-time target?