So I have been looking all over and cannot find the information I am looking for so I thought I would post a new thread. My cobalt is a 2005 base model 4 door. About a year and a half ago, I put in a new Pioneer head unit. I used the PAC interface to keep the retained accessory power (RAP) so the radio would operate just like the factory unit did. I am interested in adding an amplifier for the speakers and a subwoofer but I would also like to keep the RAP so that the radio stays on for the 10 minute time period or until I open the door. Can someone point me in the right direction of the things I would need to purchase as well as how to hook up all the components? I can't imagine it being difficult but I am having trouble thinking of everything. Thanks in advance for any help.