nesrgb wiring question - audio and palette select concerns

[laggerific]

I'm having trouble tracking down the level of detail I need for some of the wiring.  I'm very much hoping someone here has some experience with this mod, and can help me out.

First off, I'd like to tackle the palette selection switch.  Here are the official instructions: http://etim.net.au/nesrgb/switch/

So, under example 1, it looks like I am supposed to connect pins 1,2, 3 to the 3 pins on the switch.  It also appears to indicate I'm to short 3 with ground.  Am I reading that correctly?

Second, I'm not sure what I'm supposed to do with the audio pins.  O seems to be pretty clear, but the phono jack it is to connect to has 3 pins...one is ground, the others are left and right.  Can I just connect the audio out to both?  Does the nesrgb do anything with the audio like stereo tweaks or whatever?

And for the A and B (described in the pinout diagram as audio input A and B)...what does this do?  Do I really need to solder to the CPU pins?