quite old, but still works
my tips:
-use cdl and emp like ppl before said
-edit (or patch) your npcname-e.dat file so u can see difference between boxes and box-pretending mobs(tutorials are availeble over the web). U must kill with one shot only good boxes, those which hit back will not drop enchant in any way, but it hit back quite hard, so u must look out
-Always kill those box pretending mobs-when they respawn they have high chance to turn into real boxes
regarding keys:
-good place for it is loa-not many ppl a lot of 62+ boxxes
-bad point in this is: when u use key, box have chance to respawn as mob, so after few runs u have no good boxes left-u can try to kill them, or change location