The trick isn't to lift them out of the way! The NVGs stay in position and you look over or under them, tilting your head if necessary for instrument scans / emergency drills / (bacon buttie making...)
Which is relevant to your original question. Everything through NVGs is green, but the glass cockpit (which of course has to be one which is NVG compatible) isn't viewed through them so remains full colour and is as easy to read as it normaly is!
Apologies if I'm being over-simplistic.