I filled the left fuel tank with water and left it for more than a day to see if any obvious leaks were present. Fortunately, nothing seemed to be leaking so I drained the water with a shopvac and set the tank upright to dry. I'm not sure how effective this test would be since it would only detect major drips on the leading-edge portion of the tank.

The build plans don't seem to actually propose this method of initial testing, but I know a lot of builders tend to do it anyways. The real testing will be when I eventually close up final side of the tank and then do an air pressure test.

What's next? I'll be travelling for work next week, so I'm preparing a box of tools and parts for the outboard leading-edge that I can work on while I'm staying at the hotel.