If you're wanting to change your rear-end gears, you need to make sure your speedometer is going to read correctly. Everybody knows this, but nobody seems to know how to figure oout the correct speedo gears, unless you go to the dealer. I stumbled across a site that has the gears broken down into tables. The links are below.

1987 gears

1988 gears

1989 gears

1990 gears

1991 gears

1992 gears