This is probably a simple setting, but is there a setting that will allow for all wire marks to be unique per book but allow duplicates in the project?
Absolutely. In the project in question, click the drop-down beneath Project>Configuration and select Wire Styles. Right-click on a wire group and select "Properties." Change the "Marks unique by" dropdown to "Book."
Thanks Tim! That worked wonderfully. Just a note to others, that you may have to enable that setting for each wiring number group depending on how you have your wire types organized.
Retrieving data ...