I've had three 1992's (2 Caprices and a Roadmaster) and each has had to have every power window worked on, in specific there's these plastic parts that run in a track when your window moves, and they need to be replaced with a round shaped part that's not prone to failure.
I've had to do all 12 windows in the three cars.
The driver's door power window switch is bad quality. The plastic is about the same as a breakfast cereal prize in all the window, lock and seat switches on mine.
So I'd go over the power windows and see if there was anything that could be slightly broken already that you could get them to replace, like a switch that rocks too much compared to the rest for instance.
I'm only familiar with '92 non-Imps though, and maybe yours is different.