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If I were you bud. Don't look too hard into it as much as you are. Fit up the Dawes and needle valve and then go from there. The Dawes and needle valves will change the motors performance greatly and your current findings will be null. The boost readings you have are with the car stationary. Your best off getting readings will the car is moving and under physical load.
But it seems to me your on the ball and know what you are doing.