Those who have heart conditions or other medical conditions may want to skip this post.
Dear non-denominational holy one.
Economy is way up at lower speeds.
940.x miles to low fuel light
Refueled at 945.3 at commercial station

(all the way to the top with lots of time to allow foam to settle)
14.784 gallons of dinosaur juice pumped
64.28 MPG
I would estimate that would have been a low-mid 50 mpg's tank prior to mods but that is highly un-scientific. however we can now get a decent idea on fuel economy for previous tanks.