2004 chevy cavalier, class 2 data

I purchased a 2004 chevy cavalier over a year ago from a private seller. When I purchased the car an aftermarket radio was installed (which never really worked very well) and the stock radio was kept (detached) inside the trunk. Recently I decided to replace the aftermarket stereo and put the original stock stereo back in. Unfortunately the previous owner cut the harness and hardwired the aftermarket radio. After much aggregation I identified all wires and attempted to install the original stereo. I purchased a delco 24 pin gm class 2 wire harness and began the installation. Everything seemed okay minus the accessory power. From my research I understand the stock radios in gm 2000+ cars, the acc power comes through the class 2 data bus. After all my connections I'm left with two wires on the car, one (grey) I believe is the illumination wire because it gains 12v of power once the headlights are turned on. The other (purple) I believe to be the class 2 data wire. On the delco harness I'm left with amp hookups which I don't need and three acc power wires (red) I attempted to connect the purple data line to all three red acc in wires to no avail. Now my questions is, am I able to still use the radio and where would the class 2 data wire (purple) need to connect in order to gain accessory power from the data line. The only information I can find is on installing an aftermarket radio, not putting a stock stereo back into the car. Any thoughts or suggestions would be greatly appreciated.

first off what kind of harness are you using to plug into the factory radio (Metra, Best Kits, cut out from junk yard)? I can say if it is a Metra harness (71-2003-1) the Purple wire ,Class II, will connect to the Purple wire that is directly under the Orange wire (12 volt constant) in that harness (they are at the end of the connector). The Orange wire is pin B1, the Purple wire is A1.