Hi Maura.
You can control which users see the custom dashboards when they view any template by updating those user's Layout Template (E.g., members of the Policy Group, assigned to the "Policy Group Layout Template", should see this dashboard listed in the left panel anytime they view any template).
What you are wanting, and is not possible to do, is dictate on a template by template basis, which templates display the custom dashboard and which do not.
There may be a suggestion for something like that in the Innovation Lab, but I don't know how much traction it would get. A more popular application of the same principle would probably be "selectively display custom dashboards on specific projects."
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