so for christmas i got new speakers, two subs, two amps and the wiring stuff to hook it up. with that being said, do i need this special harness with using the stock head unit? trucks an 06 with only 4 speakers. thank you!

 

4-speaker systems still require a special canbus plug, BUT, can be worked around with minor wiring.

You can use the basic Chrysler plug for the speaker wires. The power wire, you'll have to tap into the cigar lighter. Pink/yellow stripe is an ignition controlled wire and is a 20A line, plenty to support the rado. I'd highly reccomend drilling a hole in the tubular dash bar behind the radio and tapping a screw into for a better ground. The OEM radio grounds are terrible and don't really offer good support for more current demanding applications.
Weedahoe has service manual downloads in the FAQ section of 3rd Gen as well as in his sig. (fyi...06-08 should have all the same wire colors)
Good Luck