I pipe clamped an emergency tire stem to a plastic hose (cut off from my wort chiller) and to the fuel line inlet (I covered the overflow tube with a cleco rubber and camped it). Hooked up my air-pig and slowly pressurized the fuel tank. Then I spritzed all connections and the fuel-fill cap with dish-soap and water. I needed to tighten a few line connections and I also needed adjust the fuel cap. No more leaks. I have rechecked that there's still air pressure a few hours later and it's still holding it. Looks good.