Crackling/"rustling" noise in Chrysler 300M
I can tell that you’ve been around cars before. One thing I do before I do anything on the dash is google OEM and look at the pathways that exist between where the fan is located all the way throughout the exits in the dash. If you need to go deeper then you should be in a position to reverse your way all the way back. Sometimes it’s not possible but that’s my first inclination.