Hello Eric, just modify your Convert Task (which you run when the drawing is released?) to hide layer on your drawing. Here are links to understand how to modify Convert Task and some layer vba example from SolidWorks help. In customer portal there are some other examples how to modify pdm tasks.
It won't hide the box, but here's a video I did to show how to get a Watermark on your drawing. You might be able to organize it a certain way so the box is hidden.