Simply not correct.. Except for the length of threads on the adapter part.. :thumbsup:
Cajun here has it..
Its important to have a correct tester. The one you describe I wouldn't trust anymore than throwing darts at a board with PSI readings on it. You could try but so little makes such a huge difference.
Otherwise, take out BOTH plugs, your gonna be kickin like a mofo, this helps to let her turn over a bit easier.. Hold at WOT, this actually lets the air in to get the reading. Has to fight through that carb your gonna be looking at a leg that may feel as though its gonna fall off to get the # up. Like Cajun said, kick untill it stops. If I remember correct I think I usually have to kick 35-40+ to get there.
RIPPEN