We took another test drive of the truck. This time it was a little longer, and in the day time. We drove it 8.5 miles in total. In that distance I used about 20Ah from the battery. Using a nominal voltage of 141V for the battery pack, that works out to be 332 Wh/mile. That is not too bad I suppose. I had seen estimates of anywhere from 250 to 400 Wh/mi, so I am not unhappy with that.
But since the thing I measure is Amp-hours in and out, that is what I will use to determine my capacity and range. Using this very preliminary data to extrapolate my range, and using 80% as the maximum depth-of-discharge (DoD), my estimated range is 54 miles. The remaining 20% capacity is a reserve that I will never plan to use, and is about 13 miles. By limiting the maximum DoD to 80%, the battery pack will last longer.
As I said, this is very preliminary, and the range will be very dependent on where and how I drive, but I am happy with this performance so far.
Here is another test drive video (youtube), about 4.5 minutes long.