As you can see, there are many boards being duplicated to form a wall.
The thing is: in real life, the middle support board is usually different for each board, like this:
So basically, I want to randomly set the Z position within the range of the top beam and bottom beam (of the boards in my scene) so that the middle support-beam is randomly positioned, reapplied for each array instance. So I went ahead and made a python script that randomly sets the beam'ss Z position from the top beam to bottom beam, and currently whenever I hit "Run Script", it re-randomly sets the position of the beam, exactly how I wanted.
The problem: As you can see, all of the array instances are the same, but I want it to randomly move the beam (a.k.a., somehow re-apply the script) for every array instance, but I have absolutely no idea how to do this.