Sun 411 External HD Case "How-To"

This shows the hole in which you need to insert something to push against the internal latch to release the top half from the bottom half of the 411 case.

It's the third hole from the back and the second down from the top. Don't push too hard or you'll snap the plastic latch. You should hear it "click" into the open position.
DO NOT TRY TO PRY IT OPEN. You'll only damage the case.
Once you have separated the two halves of the case, the rest is easy.

In this image, you can see the plastic latch. The hole in the center of the latch grabs a tiny "bump" of plastic on the inside of the top half of the case to hold everything together.