Hey @Jeff, thanks for posting!!
There are currently a couple of ways of doing this, have you by any chance taken a look at this post that @hed submitted a couple of weeks ago?? https://community.tulip.co/t/gauge-in-analytics/707/2 
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Essentially, you can add variables (or fields in a Table) that default to the limits you’d like to set and use those as the running bounds for your chart. Would that help you achieve what you’d like to do?? Let me know if I’m missing something!!
The request for SPC tools (including upper and lower limits) has already been submitted, and we’ll keep you posted as there are updates.