Isn't the tygon tubing 1/4" ? If so, you'd need a 1/4" festo rather than the 6mm Festos that most of us are using.

For fueling, here's what I do on all of my jets: 6mm fill-line from UAT goes to a Festo ball-valve ; the other end of the ball valve has a short length of 6mm tube that has a fuel-dot in it. To fuel up I remove the "stub" length of 6mm, plug in the 6mm line from my fueling can, open the ball valve, fill everything, close the ball valve, remove the filler line and put the stub back in.

This method has been leak proof for me for a long time (7 years, in the case of my Bobcat), and has a level of extra safety in it in case I screw up - if I forget to put the stub back in (happened once when I got distracted) the ball-valve still closes the fill line off and no leak results ; conversely if I put the stub in without closing the ball-valve, it's still sealed too. So, I have to screw up TWICE (ball valve left open AND forget to replace the stub) before there's a problem.

If the above is unclear, lemme know - I can snap a pic later and post that if need be.

Gordon