[graysky]

Actually, the default option on a git package is to pull down the latest commit despite the fact that the PKGBUILD contains an older commit, so no worries there.  I guess I could modify the text to:
1) Point the git PKGBUILD.
2) Show how to change the source repo from the official one to a fork which presumably people modifying the source would do (ie fork their own copy and build from it).

Is that more aligned with the goals?

That means users would have to commit the changes to a certain repo just for the sake of compiling their local copies. That's not really the goal of those docs. Isn't it possible to point pkgbuild to a local folder on the fs? 

Yes, it can be done.  Let me edit my file accordingly.  Will update when done.  Interested in your feedback.