I've never worked on a stratus, but most car doors are held on by a few hidden screws. Some are covered by a piece of plastic that you have to pop off, and others are just out of plain sight. Make absolutely 100% sure that you have unscrewed all of them and then the door is usually just held on by clips that will pop out of place if pulled on hard enough.
To be safe I would try to find someone that has taken a Stratus door off before. Maybe they can tell you exactly how to do it. I'm only speaking from the experience of taking many doors off of many cars.
Try contacting a crutchfield adviser on chat or call the 1-800 number maybe they can give you some better guidance
Good Luck try not to break anything
Try this page:
http://www.crutchfield.com/App/Support/SupportHelp.aspx
Loud and Nasty!!