Audio Systems: Speaker Wiring on 2006 Jetta, speaker wiring, professional installers

Question
I've been finding out a lot of things about the 2006 Jetta as I'm about to get ready to install aftermarktet ones. I heard that from sources onlne that there is a amp that is built on the speakers in the door is that true. Next I want to know how to wire the speakers onto the new speakers. I see that there are 4 different wires connecting to a clip. I know I have to splice it and connect them but I dont know which ones to connect into the new speakers. Thanks

Answer
I would just look at it in person and (using common tools) I would determine which wires were what.
You might best spend your time honing your 'factory wiring chasing skills'. Then the vehicle you work on is a non-issue, eh.  :D
There are 1000's of vehicles not fully understood at a glance. This understanding of (and determining why) it works is the main difference between professional installers and the plethora of 'immitation' installers that are out there.