I have information to contribute to the profile of Margaret (Jones) Griffith. This is what I can add:
These are the sources I am using:
Should I contact one of the pre-1700 projects or know about any style guidelines before proceeding? Thank you!
Seeing her profile is managed by a Project, you could post a message on her profile page, indicating what sources you have, and if those are considered valid sources by the project before proceeding.
Or on the profile page, you can click on [send private message] after William Penn and Early Pennsylvania Settlers WikiTree