With a gas tank of no more than 4 gallons and a 127 CI Ultima engine, I won't go too far... I need to install a fuel gauge and wanted to ask if anyone can recommend the easiest way of doing it. Thanks.

 

This may help, but you will need to repaint your tank;

 

Interesting solution, thank you.

 

But no need to drill the tank, you can install a T at your bottom valve and run a hose U to the cap.