Sounds like a great idea if you're doing large quantities and can set boxes on a bit of a pedestal. Something like two pieces of wood to keep the box from touching the ground and allowing airflow. I've never dried that much at one time but for what it's worth, boxes have a natural desiccant quality control because you can open and close them and hanging them can be an option. Contamination is often an afterthought because it can be grown outside yet worried about stuff collecting on the buds...why worry about it so much? Show me a sterile bud....if possible.
(Put a rod inside widthwise and hang)