Hanging template for Large Minifig Case
Since no answers were given for two days, I'll convert my comment to a full answer:

If you haven't found anything yet but have access to a photocopier, you could try making a copy of the back side that contains the eyelets. The resulting print will be a 1:1 paper version of the back side, which you can tape on the wall intended for hanging the cases and drill through the images of the eyelets: 

Be sure to align the sheet correctly, using a bubble level or such.