I can add a to the profile of Hannah Spiers or Spears. This is who 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!
If that profile is not managed by a project, you do not need to contact one.
The sources seemed not to be primary sources, primary will be better. But maybe you find some if you search with the knowledge of that source.
But I personelly think that for the first step the source is ok.
As long as you follow the styles, standards and sourcing expected for a pre-1700 you can add the profiles.
If you have not done yet, you should read this page before you start:
https://www.wikitree.com/wiki/Help:Pre-1700_Profiles