Thanks ronster. Although not what I was looking for, this is fabulous information that I will archive for future reference.
Now, as an update to my inquiry:
Actually, I just drove the car for the first time after the hack and all four wires are performing their basic function, i.e., scroll up, scroll down, reset and speed gong.
However, I just can't turn on "Display A" as referenced in the Owners Manual! What is with that? Can people with the 4th stalk do this? I can think of the following possibilities:
1) The factory wiring for the OBC is more involved than the hack, hence, the hack provides limited functionality.
2) The 4th stalk is more that a simple SPQT (single pole quadruple throw) switch. In other words, it does more than just short one of 4 signal wires to ground. If so, does anyone have the switching diagram for it?
3) What I got is all there is to the OBC and the factory illustrations are not applicable.
Any and all input would be appreciated.
TIA