I found more useful information on various forums than in repair manuals. As for the box it's really up to where you want to use the space. Again the forums have a lot of great ideas. For your amp you will need power from the battery, ground to the body, and a switched power source for the remote turn on on your amp.for the signal to your amp you have a few options. The easy / cheap way is to use a line out converter. You wire it up to your existing speakers then it provides RCA outputs to run to your amp. I did this in my 2011 JKU with Infinity system.the factory system uses a low pass filter for the factory subwoofer. you could tap into those wires,they run along the passenger floor and are grey with a black stripe, green with a black stripe for one channel, and grey with a white stripe, and green with a white stripe for the second channel.its a dual voice coil sub. or if you want to use your own low pass filter which is often found on your amp you could tap into the front speakers. Do not tap into the soundbar speakers because they are high pass filtered and have no bass.