So, you're saying when you hit the down switch to roll the window down, it'll keep rolling down after hitting the switch? If so, thats normal. Most newer cars do that. The G1 was so far ahead of its time, what ever the newer cars has, the G1 Legend had it first. If you don't want the window to roll all the way down, try not to press the switch hard. Give it a light tap.
If you hit the switch that turns all the cabin switches on, and it starts to roll down on its own, then it sounds like the switch is bad. If you have a local junkyard near you, you can probably find one there and replace it. Not sure what model you have (Coupe/Sedan), if its a Coupe, you can grab the master switch from an 87-90 Coupe. If its a Sedan, you can grab one from an 88-90 Sedan.
If you hit the switch that turns all the cabin switches on, and it starts to roll down on its own, then it sounds like the switch is bad. If you have a local junkyard near you, you can probably find one there and replace it. Not sure what model you have (Coupe/Sedan), if its a Coupe, you can grab the master switch from an 87-90 Coupe. If its a Sedan, you can grab one from an 88-90 Sedan.