Rearset DP by
AntiHero-X, on Flickr
Your rearsets will have the tie rod (#5) mounted on 'em. (I believe it's mounted on the back side). What you need is #8. I'm not sure if older DP rearsets have both links or if it's just the new ones. If it's just the new ones, someone on the forum will most likely gladly sell you the piece. If your dealer installed the rearsets, you might want to contact them to see if they have the piece.
Note: there are two gearchange pushrods (#12). One is 103mm the other is a 93mm. So long as you keep your footpeg in the same position it's currently in, the GP shift swap won't change the length required. And yes, the quickshifter will work just fine.
Also, the GP shift con rod (8) can be installed with bolt/nut #9 & 11 in the hole that it's mounted in in the picture, or, for faster shifting you can mount 8 (using the same bolts) in the hole just under where it's mounted in the pic. I'd recommend the lower hole. The bolt (11) rubbed my swingarm and had kind of long travel. The lower hole = crisper shifting, but makes finding neutral nominally more difficult.
Edit: After re-reading your initial post, it's unclear if you actually have DP Rearsets. If you just have the standard "rearsets" that came on the R--which are the same as the S/base/tri (I believe)--there is no way to just flip a linkage to get GP shifting. You'll have to buy a pair of rearsets that allow for this.