Aha, so that just means you connect both ends to that 3.5mm connector which goes to tuner (and perhaps delegate some button to mean 'shift', if that makes sense in your particular layout).

Also note that currently tuner reports measured resistance whatever it is, but accepted values in player software are fixed (untill Mark attacks the stalk(s) as a part of traslation function of his Hijack kernel). So, at the moment, the only way to emulate Sony's stalk directly is by changing actual resistors. However, I would bet that within, say, two weeks we will have something more elegant from Mr. Lord's workshop :-)