Drained 17 gallons of fuel back out of the tanks after having them full for 4 days with no leaks. I figure it will be a few months until all the FAA paperwork and factory checkout can be completed so I didn't want it sitting in there that long.
I pumped the first two gallons out into my gallon jug and the fuel flow meter showed 2.0 gallons, so that's good and, the sight tube showed exactly 17 gallons, also good.