The battle box is as crummy as I thought it would be. I'd rather use this layout and roll the dice individually.
´
You don't need to roll them individually, you just need a way to tell which die goes to which position on the chart. You can use different colored dice or write numbers on them as in the picture below. Notice that you actually only need 6 different dice, as the first 6 slots are identical to the last 6 slots.