Procedure for reassembling individual chapters

From the helpx:
"One of the documents added to a book file is the style source. By default, the style source is the first document in the book, but you can select a new style source at any time. When you synchronize documents in a book, the specified styles and swatches from the style source replace those in other booked documents."

Due to various factors over several years work in this, I'd prefer ID not to overwrite any of my work or formatting without stopping and prompting before doing so. I resist this automatically applying the first document's settings as the style source to the next 40-odd chapters. That should be an option, not a default destruction. This is a very manually constructed book, without uniform use of ID's myriad and overwhelming (to my thinking/approach) features, which are designed by ID to save time when you know your approach globally, but were not employed to help me interate in the process I used at the time and not adequately veresed in their use.

I'd rather assemble all 40-odd chapters together in a way where ID alters nothing, other than adding correct pagination. It's 400 pp. with hundreds of sidenotes and illustrations, meticulously constructed and placed, and which slowly evolved amid reasearch in all areas. Had we known more of the answers to what we wanted (from the design and the book's content) at the outset, it may have been more conventionally constructed.