The key is that quick-disconnect fitting, which is described as a “Schrader” connection. However, this is not your garden-variety connector like on a tire.
Anyone happen to have one? The gauge needs to read suction, too, for this application.
So are you just wanting to just fully pressurize? I have nitrogen and a regulator. What kind of schrader is it? Is it on a flare fitting or something else?
We can hook it up to a magnahelic gauge to see what pressure is is.