Personally I think your going about your quest all wrong. If you want a decent light '80s road bike you simply need to go buy one. rather than look for some 'bike I had once' just find a bike that fits well and has decent frame and components.
There are several things I do not understand about you postings. The dream bike you are hunting for is described as possibly aluminum but had safety levers and stem mounted shifters. Those two items don't generally go together on a quality bike unless someone cobbled something togather in the garage.
Why did you ditch the Trek and Diamond Back?
Setting out on a quest to find a bike you have some vauge description of sounds more like an excuse not to get a bike.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk