Two monitors, side by side

I managed to pull my old CG-21 of the moth balls, to serve as a second display - how could have I ever lived without this convenience? Crazy. Of course, first thing I did was to try to make it "look" like my NEC PA271W. They're both LCD monitors yet, at the same chromaticity and Luminance, they don't look the "same". One is "reddish" (CG-21) while the other (NEC) is "greenish". Any suggestions? / Roger