I need to combine two custom templates into a single template, so that all the styles from both templates are available to users.

Word wants to overwrite the styles because they were created using the header styles; I have tried updating the styles so they are based on "no style" but it still associates the styles with each other and overwrites them.

How do I break that association so that Word will view each style as distinct and allow users to select both of them in the same document? Is there any way to do this automatically without having to recreate the full set of styles from one of the two templates?