The color is called "Blue Nova" and it's a 1992 model year color. Last year they had the model names on the down tube.
I was gonna swear it was a 90 or 91, but thats what I love about you GM1230126, is there anything about GT's you DONT know...lolz?
By the way, I saw that Lightning you just sold...FREEKIN CLEAN, looked almost good as NOS.
One more thing, I'm building my dream garage, I have two of the three bikes I'm after (my Psyclone, and Lightning), sometime in the future (6 months at least I estmate) I'm looking for an 18" polished Zaskar (frame preferably - painted is ok, but again prefer polished) between 93' and 98' (no u-brake frame). Anyway, just thought I'ed mention it for you to keep in mind.
97 GT Lightning
94 GT Psyclone
92 GT Richter 8.0