I quit making uniflow tanks about 3 or 4 airplanes ago. They just weren't needed. I run a two line setup when I have easy access to both lines. I'll fill through the feed line. I pull the line off the carb or remote needle and fill until I see fuel start into the muffler line. The muffler pressure line goes to the very top of the tank as any overflow would. The tanks run excellently well. The uniflows couldn't run any better since there is no room for improvement.

I've been running a similar setup with just one modification in both the Ultimate and the CAP. Both cowls give no easy access to the lines. So.......

I've placed a T in the fuel pickup line between the tank to the carb. The branch line simply goes from the T to a hole in the side of the cowl. The hole is just slightly larger than the silicon fuel line. I make a poor man's fuel dot setup with the size of that hole. My line plug does what every effective plug would do, it slightly bulges the line. I size the hole in the cowl so that bulge will slip fit through it. When I push the excess line back into the hole, the bulge pops through the hole and keeps the excess line inside the hole while the head of the plug keeps the end of the line from going through the hole to be lost in the cowl. Obviously, the head of the plug sits there outside the cowl, but it's not exactly noticable. And it works great. Works just like the expensive fueldot hardware and actually costs nothing. After all, it's just a hole and a plug I'd be using anyway.

To fill, I grab the head of the plug and pull the excess line out to grasp it. Pull the plug out and fill. Stick the plug back in the end of the line and then push the excess back into the hole.