re-use 101

[Joel]

I am using Frame 8. I have a set of seven manuals that are close to 100
pages each. Many sections of these manuals are identical, some sections
differ in detail in minor ways, and fewer sections differ in more
substantial ways. Currently they are all Frame books with each chapter being
its own file within the book. There is no re-use of anything at the moment.

This is becoming increasingly burdensome to maintain, as a change to
something that appears in all seven manuals requires me to make that change
manually in all seven files. I would like to get to re-use, or
single-sourcing, but I’m puzzled as to how to get there. Would the best
strategy be:

(a) To use conditional text and generate several versions;

(b) To try and convert everything to XML and sew things together based on
individual XML files;

(c) Something else?
I have zero XML knowledge, and whenever I read about it, my head hurts. I am
willing to learn, but the benefit needs to be commensurate with the pain
involved in learning. I’m looking for the simplest solution that allows for
some common source material using my existing Frame configuration. Ideas are
appreciated.
Joel