Took me and a buddy 2 hrs my first time back in 2010 but now it takes me 20 minutes including the DCI's. Take your time and double check everything. One more tip is after you think you installed the JB4 correctly, re-connect your battery and see if your car starts. If it does thats good, then hold down on both the steering wheel volume and channel buttons to make sure the JB4 is active. If all checks out then put back together your car. I still do this after 3 years of installing my Juice Box just to make sure it's installed correctly. Follow this N54tech thread for details on the steering wheel controls, etc.