I did the upgrade about a week ago and it's working great.
I've found that it helps to remove the bottom cover first to avoid breaking the locking latches on the top cover.
I did this install to control an aftermarket Pioneer AVIC-D3 unit using the SWI-PS adapter. Out of the 2 wires you need to run, you simply ground 1 (any one), then connect the second wire to the white lead of the SWI unit. (Add diode to control mode button, program swi for version 3, then have it learn the button commands)
With the help of this writeup, I also performed this upgrade on my Honda Pilot LX to control an aftermarket radio and by purchasing the EX radio controls. The Pilot buttons didn't come with a connector harness, so I had to run the wires into the steering reel.