My top skin is more or less to plans, but there are a few things to note from this step. First, there is an access hole in the outboard rib, normally an area filled with foam. After some discussion, John and I decided to leave this area open, and fill it later. For now it will provide an easy access point to one of the common sources of fuel tank leaks. After the tanks are fully sealed we'll discuss what to do with it.

Second, you can now see the accessories installed in my tank. In addition to the usual fuel line elbow in the sump, there is a return at the top of the tank. I'll use a solenoid to switch the return, which is the same thing John does. There has been a LOT of discussion of how to do this - I've agonized over it for THREE YEARS, and discussed various solutions with all the experts. My final conclusion has been that there IS no "perfect" way - every method has pros and cons. I chose this method because it seems the most natural to me, and thus I believe that during a failure I will be more likely to intuitively select the right response than if I'm relying on a system that makes less sense to me in the first place. Designed for Humans.

You can also see the plates installed for the level sensors. There are five in each tank - four in the tank itself, and one in the sump. The original Cozy just has sight gauges. Many builders install level sensors, but there are accuracy problems, especially with ethanol-based fuels. I chose a middle ground. In case you're curious, the part I used is a Cynergy 3 RSF86Y100R. Digikey carries them for $14.83 apiece, with a bit of a discount if you buy 10. But apparently Digikey won't be carrying them much longer. If they run out, both Allied Electronics and Newark show stock for similar prices.

I'll measure the weight next time I think of it. But as for that, they feel pretty light, and capacitive senders aren't exactly feathers anyway. The cost is probably comparable, if a bit more because I used five sensors.