Welcome onboard.
This recent topic from the general forum gives the step-by-step:
http://www.contour.org/forums/ultimatebb.php?ubb=get_topic;f=1;t=013263
98 Mystique LS v6 atx 110,000km
97 Contour LX v6 atx 125,000km
stock CD on LS, cass on LX
spoiler, tinted windows on LS only
4 wheel discs on LX only
All other available options on both
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