2003 Dodge Caravan blower motor

I'd request a second opinion from a different shop. Your mechanic may just be assuming it's built like GM vehicles and the service procedures are the same. Chrysler usually lays out their systems with an eye toward serviceability. I don't recall ever having to remove the entire dash assembly to get to the fan motor, and certainly not to the resistor.

By the way, there's a thermal fuse built into the resistor assembly. That usually overheats due to the motor becoming tight and drawing higher than normal current through those resistors. Many people replace only the inexpensive resistor block, then wonder why it fails again in a few weeks. In later years they used a computer module to control fan speed to meet customers' silly demands for infinitely variable fan speeds. That is an expensive alternative to the relatively reliable and inexpensive resistor assembly.