Believe it or not, there's a sticky about this at the top of this audio & electronics forum called "2000, 2001, 2002, 2003, 2004 radio info! " and it contains the info you're looking for.
Problem is he doesnt' say what year of Jbo he has, that sticky doesn't apply for below 2000 cars, but still just search

It is your friend
Crap i cant edit and i didnt mean to hit enter. But ive searched, headunit install, getting to headunit, headunit(looked through a bunch of pages), wiring headunit. and a bunch of others and no luck.
bmxbikes h wrote:96
a 96 what?
cavalier? sunfire?
I had a 96 sunfire once and those are easy ... open the glove box .. remove two screws on the left of the glove box, remove that bezel and you can access the head unit ..
can't help you if its a 96 cavy though .. I think you have to pull out the whole dashboard
Why did they make the cavalier so much more difficult to work with than the sunfire?