Plumbing down to the fuel drain valve required some "fuel line Origami" to make the bends, keep away from any control cabling, and maintain a gravity flow down to the drain at the lowest point. This was challenging but ultimately rewarding. I learned how to assemble Swagelok fittings and work with 3/8" OD aluminum tubing. A tube bender made much of this work easier.
From the drain valve tees, I then plumbed up to the fuel selector valve ahead of the flap handle. Positioning the selector in just the right place was important to me. I want it to be close enough so I could reach it while in flight with my belts cinched, but I also didn't want it too close to the flap handle, and I want to leave room for a center forward console. The console may hold switches, indicator lamps or a fire extinguisher.
I also wanted to make sure plumbing to the selector and from the selector to the filter/boost pump assembly took advantage of the openings in the forward cage tunnel.
