On my 2001 the rubber accordion between the door jam over to door is partially removable. Your able to take the rubber grommets out so its hanging on the wires. There are a bunch of wires that go through it but room enough for another set of speaker wires. This how I've done it with 20 cars or so. Don't worry about the Infinity system wires, run the new ones from the new amp to the new speakers. Installing a system into any vehicle is time consuming, panels will have to come off. On some I take the whole interior out to make it easier.