How do you Remove and Replace battery in 2003 Olds Aurora?

It is under the back seat. The seat snaps off--there are about 5-6 snaps in all--and then you just lift it all the way out of the car (real simply). The battery is right there with plenty of space to work with.

***make sure you re-attach the vent lines that are connected to the battery to make sure you don't get toxic fumes inside your car! There are 2 of them, little black tubes.