IIRC you use the "weather" rules. The night vision kit simply modifies the ranges at which you can see/fire (TI is treated as normal "daylight"
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. On top of this there's -2 on the CVs for fighting at night. I don't recall this being modified by night vision kit.
I considered a night action for my Arab Israeli '73 games, but the rules as they stand would be worse for the Syrians, even though they had more image intensifiers than the Israelis. Low/medium CV armies would find attacking at night difficult I think.