Nah, you don't have to worry about the forward tilt at all. I just meant that it makes the mount eccentric rather than concentric such that you're now balancing on top of the pivot which means the monitor is putting leveraging force on the tightening of the bolt. Since you're in portrait mode the deviation is less anyway, even though you're using 30" monitors.
Based on this pic, am do I need to loosen the top screw so that this bolt is going through the hole of the mounting bracket, which is below it, with a slight gap? Right now that is as far as the bolt will go. I tried loosening the screw at the top , but it's pretty firmly screwed in place.
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