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Neither. Use 2 wrenches, one on the flats just to the the right of "1" and the other on the flats at "2". The hose will seperate just about half way between the points you show- about even with the end of the lower arrows top line. When restalling the second stage, be sure to lubricate the oring located inside the hose just to the right of your "1" and do not over tighten the connection on either end. The orings do the sealing, more torque does not mean a better seal. All you need is the connection to be tight enough not to come unscrewed by itself. If it leaks DO NOT tighten more, find and fix the problem. More torque is never the answer with leaking orings.