Well... I did the trip out and back, starting with 1/4 tank. Disappointing 64 mpg round trip. Then I filled up, and the Scangauge was underreporting my mpg. I topped it off and drove around the block and came back to top off again - I've never filled it this high before. I can be sure this was not a short fill. 886 miles, 12.2 gallons = 72.6 mpg! And that means 1st place in the challenge. I was expecting to need 73, but the extra distance and better-than-expected fillup made the difference.