I used a single edged razor cutting from one side to the other starting in the middle (reversing for the other leg of the first cut). Then do the same from the center of the first cut, completing the 'X'. I wouldn't pop out the plugs but if you want to do that remember little bugs can come up through those screens AND you might get some 'splash' mud and crap in there. The 'X's on mine do not let anything in but lets water drain out (they are stiff enough as to not 'droop' in the center). Whatever way you choose to do it, just remember if you completely remove them plugs, you might have issues with what you install.
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