if you typed in "video on a triple 20g aquarium stand build" I doubt you'd come up with much, it's a bit of an oddball one. the trick is to incorporate the design and build method from the thousands of stands on line and use these methods on your own stand. most people just go to joeys builds, he's done dozens and dozens of them.
like I said, the important thing is that your screws shouldn't be relied upon to do any load bearing, they should only be there to hold the structure together.