Help please 2001 Grand Am stereo wiring

[Insomniac51]

I am trying to put an aftermarket stereo in my son's 2001 grand am. The stock stereo harness has been cut. I bought the Factory 2001 Grand Am Harness Metra 71-2003-1 & a Class II Data Bus interface adapter - GMOS-01 from Metra online. I have the GMOS-1 all wired up and ready to go how ever the Metra 71-2003-1 wire coloring does not match. That is not the real problem. I found the schematic as to what wires go to where except the 2 purple wires. Here is the schematic. http://ww2.justanswer.com/uploads/GU...8_102526_B.gif The first purple wire is in spot A1 on schematic and says it is "Class 2 Serial Data" the second purple wire is in spot B6 and says it is "Gain Control Signal" How do I figure out which is which and what happens if they get hooked up backwards?

[xeroinfinity]

idk if you got this taken care of but here are some better wire diagrams with color pics

http://www.bulldogsecurity.com/diagrams/

And Welcome to AF!