Greetings! Seems as though the missus wants to hook me up with an EoTech holographic sight for my AR for our anniversary. Currently I have an MBUS rear flip up and an f-marked A2 up front. I've seen...well, I've *heard* of co-witnessing. Can I do that with an A2 Will I need anything special to mount up the EoTech or is this your basic drop in? I've an a3 flat top. I think eventually I'll swap the A2 for BUIS on some kind of rail... But don't want to scare the wife with too many goodies at once. Your expert guidance is greatly appreciated!