Crossfire = Unique beast, Designed by Chrysler... engineered and built by Merecedes.
Your friend doesn't know diddly. The Crossifire is based on an SLK320 pan (chassis floor pan) and then becomes completely unique from there. Suspension parts are from both the C and S classes. The driveline is almost entirely SLK. Lots of body parts, interior pieces and trim are specific for the Crossfire. Many of the systems are found in both the C and S classes.
Don't be deceived... it's a Crossfire...