Step 2: Break the Box: Getting into the Adapter
So, I managed to create a deep groove around the entire seam w/ a chisel. The groove helped to safely (and, unfortunately, extremely slowly) hack-saw my way through the plastic shell (not any further than the thickness of the plastic). Even at this point, the two shell halves remained attached to one another. So, a slow and steady twist of a broad flat-headed screwdriver at each corner cracked something inside to enable the box to finally open.