Hi There,
I may not have the exact answer you need as we have something similar, what we've done is within the XML dashboard is pass a token from the search into the rangeValues option to set the upper limit, however this does not display the final precise number in the gauge... merely the last whole number then a gap. To resolve this we use the same token to display the upper within the title bar of the gauge
name="charting.chart.rangeValues">[0,$limit$]
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