01clsblackUOP

i want to replace my stock component system with a aftermarket one. I looked at the wiring diagram from silverknight and realized that there are only one pair going to both the speaker and tweeter on each side. So does that mean there is a crossover somewhere between the speakers/tweeters and the amp? I don't think that there is a built in crossover in the amp cuz the wiring diagram shows only one positive wire and one negative wire output for both the tweeter and speaker on each side of the car. I want to use the factory wiring to hook up my new component system to my new amp. i also want to keep the crossovers that came witht the new speakers in my trunk. can anyone help?

Or maybe i can just install the crossovers in the door and use the wire running between the speakers and amp to connect the crossover to the new amp. Then get new wires to connect the tweeter and speaker to the crossover in the door. But before i can do that, i need to know what else is between the factory wires?
Btw, i want to completely bypass the factory amp.