I picked up a GT talera on craigslist a few years ago. Its the only old GT MTB I have seen without the distinctive extra triangle under the seat. It still has the GT badge at the back of the to tube however. I think it was late 80s. Predated bikepedia, so I don't know for sure. I really liked it, but had no real use for it, so I sold it. Was kinda beat up, which I liked. It also had biopace, which I never noticed while riding.
Although they we not quite 1980's I've always like the look of Cannondale headshock bikes. No idea if they were any good or not, but they look great to me. Very subtle, not like a regular shock.
(Not my bike!!)
One thing I have noticed in these old MTB pictures is how nice the gumwall tires look on a mountain bike.