Not sure about how it comes off but I installed an new radio/mp3 player in my Durango and when I bought it from Cructfield (
http://www.crutchfield.com) it came with all the instructions for the Durango and even the exact wiring harness so it was as simple as plugging it in and connecting a few clearly marked wires.
I checked the site and they don't give this stuff away unless you buy a radio so if you havent bought it yet I would try there maybe.
Good luck.