Comment If the cops are looking, it's NOT too late (Score 0) 512
Put some termite on it with a very sensible movement fuse. So the thing couldn't be moved anymore.
Termite is not a explosive, so it's no damaging. It will turn instead the box in a melted slug without remision. It's used for heavy-duty-rapid-outdoor-emergency iron soldiering.
Of course tring to avoid the in-course melting process could be very hazardous, and imposible. Put the termite just over the HD, for the extreme paranoid.