Here's the deal: I have six folding, stackable bookcases that I want to stack up and make a "wall" of shelves, three wide and two tall. I want them screwed to the wall (the top ones) so they don't tip over.

What I want to know is, if I stack them and fill them up with books, can somebody just take off a few books and secure the shelves, or do I have to have somebody come and do the securing BEFORE I load them up with books?

It's like pulling teeth to get somebody (that knows what he's doing) to come do a little job like this, and I want to be ready. But I'm also anxious to get this project underway. My son said he'd stop by next week-end (that was three months ago.)

This is the shelf: