I guess my central question is, what is the best way to make non-destructive changes to an assembly/simulation structure?

Sorry if this is "old hat" to most of you!  I've been out of Solidworks for a few years, and I'm now struggling to get back up to speed.  I'm still running Solidworks Premium 2017 SP05, with the static-simulation capability, in a single-computer configuration -- no PDM here.

What I've done in the past (as near as I can reconstruct) has been to use "Pack and Go," changing all of the file names appropriately with Search/Replace and saving them to some new folder in hopes of severing all connections to the previous version while preserving all the linkages.  (I do use a fair amount of in-context designing, so the linkages between parts and assemblies must be preserved!)  Then I would make my changes to the new files within the new folder, thereby creating a trail of independent revisions.

My recollections are a bit confused, however, because I've worked with 2014, 2015, and 2016 before this version.  I have a vague recollection that Dassault managed to "break" Pack and Go and repair it several times over those years, and I'm not sure where I am with 2017.  (I do remember that Pack and Go crashes SolidWorks 2017 if you tell it to save to ZIP file, and that it cannot be prevented from saving all the simulation study results unless there is only one study in 2017.)  I also have a vague recollection of using Solidworks Explorer change file names while preserving links, but I'm not sure in what version I needed to do this.

Any clarity on the history and, especially, on how best to accomplish my goal in 2017, would be most appreciated -- John Willett