I never had the opportunity to replace a fan switch on a Challenger so I will not be much help, but it appears that your assumption is correct. I suggest that when you pick up the switch you also buy new clips that most likely hold the headliner up and ask about what tool you need to remove them. Most interior panel clips on modern equipment and vehicles are considered "one-way". When you remove them they get damaged and are not meant to be reused. They are one time clips. With new clips you will be able to put the headliner back up as new and keep the integrity of the machine. It will look as if it were never apart.