[JRTJH]

If you decide to drill holes in the bottom of the boxes, consider where you drill them. If they will cause the contents to drain onto the steel crossmembers of the battery tray, should the battery "boil over" you'll have acid leaking onto the steel. Not a good idea for something that isn't checked and cleaned often. If you can drill them where any water would drain into the open space between the steel rails, problem solved.