A:AnswerHi.
I had the vehicle professionally installed by Best Buy Geek Squad.
The best thing is to verify with Best Buy if your vehicle is compatible with the Viper model and they can answer the questions. I used Best Buy live chat for my answers, or talk directly to vehicle alarm tech at store depending on locations.
Another option is to call Viper directly.
Good luck.
A:AnswerI believe that a 2005 Chrysler 300C is compatible if they use a THCHN1 T-Harness ( SKU:6143851) but the installation tech should be able to confirm this.