Should I be able to change only the text on a TKB template?

I want to change the headings on one of the TKB templates from

• Diagnosis, Symptoms, Solution to
• Description, Symptoms, Solution.

Is this something I should be able to do from the Text Editor in Studio? I can find the right string, but I don't seem to have permission to modify and save it.

I see in another article that we can't actually create TKB templates or modify existing ones (without Professional Services), but I only want to change the heading text.