Here's an interesting post I found: Fiero Power Window Switch Upgrade
For this upgrade, the writer obtained a "one-touch module" from a 95-98 Camaro, and wired that to an existing switch. Unfortunately, it's a little light on details. While the add-on modules I mentioned above are meant to be used with simple up-down switches (they change the behavior so that a momentary push makes it go all the way up/down, and to stop part-way you need to tap it a second time), I'm not sure how this module would work with a regular switch. Does anybody have (or did have) a 95-98 Camaro, and can tell us if it worked that way, or had the dual position switch like the Leaf's driver side window switch (push slightly for normal use, push further for one-touch)?
Also, I would have liked to have seen a "before-installation" schematic of the Fiero's window switch, so I can see exactly how the module was inserted.
Anyhow, this shows us another possibility of how this mod could be made.