[Balf]

I took on this endeavor as well. The steering wheel controls for the radio only have 3 wires - swc1, swc2, and a ground. I had to follow the wires to see where they go to, it took a while.

There should be 3 remaining wires/signals that pass through the terminal and goes straight over to the right side. Once they pass through the clockspring, the wiring heads up to the gauges (newer cars only). Once again, there was no easy way of figuring it out. I took some close up pictures of the SWC pcb with the traces them and mapped it out.

Which set of buttons do you have? There are many variations. I have full controls on the left side of the wheel, but on the right I have everything but the push to talk button.

edit: Also, if the wheel is from an AT car, there should be some wiring there for the paddles. Those wires should be easier to follow and rule out.

double edit: I forgot there is also wiring for illumination, 2 wires. All the buttons are lit, so it passes through the left set over to the right side of the wheel. If you have the physical buttons opened, you can see which wire traces go to the leds. I'll try to round up some info i found useful.