Thats not accurate either sean, you have to fill all the way up to the click, run the tank out, fill up at the same pump and then do it by hand.
Technically you don't need any of that. Digital DIC tells you how much gas you've used... mine does anyway. And I reset it every time I fill up. Based on what it says when I fill up, it's pretty damn accurate.
So technically, I reset my fuel used, and my trip meter, and then run out a few gallons. Math.
If yours is accurate it is the first one I have ever herd of being right.