The VIN in and of itself tells you nothing about the car color.
Yes, at one time is was possible to look up a VIN and correlate that to a car and determine it's color and options. I doubt a dealer can do that on a Fiero though, I don't think they would keep records that long. You can try Pontiac Historical services, but it's going to cost you. Best thing is to look for that point code under the hood. Based on the fact that you are just looking at a car it's possible to find out more from the VIN, but probably not worth the effort,