How do you add true position when using the tolerance analysis extension (TAX)

Hello - I am using the Creo Tolerance Analysis Extension with Creo 6.0.  How do you select a true position callout to be included in an analysis?

Per the reference guide this is possible, but I cannot find any tutorials or instructions on how to do this.  I have spent 2 hours on several scenarios within Creo but I am never able to select the true position callout to be include in the analysis.