RE: 99 Durango blower motor replacement
Yep. Unfortunately, you take out the dash. So... once the dash is out, make sure you replace the AC Evap coil AND the heater core because you do not want to have to ever take the dash out more than once.
If you do this yourself, it's a 2-3 day job. Pick a long weekend and label and bag all the parts and screws as you remove them.
I'd strongly consider paying a repair shop.