Hi @Anonymous,
I see that you are visiting as a new member. Welcome to the Autodesk Community!
This can be done with fields just like you are doing with your other titleblock information.
Simply create a new field and point it to the viewport frame. Then select the scale property.
An even more elaborate way to do this might be to use the SheetSet manager and create views with callouts.
I made a quick video of the first method for you.
Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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