I've been searching around for this info but it is very elusive. Best hint I've found so far is that you may have to remove the instrument cluster, which apparently isn't that difficult on your car. I'll keep looking for you. You may have to ask the Parts Dep't at the dealer--whoever is still servicing Saturn in your area.
It's pretty easy. First remove the "A" piller windshield trim panels. Then remove the top dash panel. There are no screws, it's all push pins so you just need a tool to pry it up. The sensor is removed from the bottom of the top dash panel with a half twist.
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