I've pretty much confirmed my suspicions. I found the schematic for the 370.
Pin 6 (pink) goes to the source, menu up and menu down buttons. Pin 16 (blue) goes to volume up, volume down.
When I was soldering the two resistors to the white wire, I'm pretty sure I overheated the resistor. Now I should just be able to put in a new resistor and then I'm off to the races.
I love learning stuff. Kinda makes my head hurt, but it's pretty cool anyway.
