Centre stand the beast on a level surface and use a thin block(s) of wood to keep it from dropping, as Charlie says, there's things in there you don't want to muck up. I also use a hand lever (pry bar) to raise and lower the wheel as needed to align the bolts holes when refitting the replacement shockie. Remove the right hand side cover carefully so as to not break off the rear end plastic stud. Some people, myself included, have fabricated a metal stud from a bolt and use two nuts to hold it to the side cover. It acts as a replacement pin when you get ham fisted and break it off. The lower plastic bit that clips over the rubber schnozzle on the frame is easily broken. Both of mine have been super-glued several times and are holding up, but just. The seat will have to be hinged up to access the inner top nut (use a 17mm socket and ratchet and a 17mm box end spanner), and if you have pannier mounts the right hand side mount will have to be unscrewed. You might as well just whiz the whole mount off as it makes it easier for the shockie to clear everything.
Re-installation is easy as. Give the 10mm diametre bolts/nuts a good firm tighten. There's a torque spec but 'feel' will do the job. I also have a Works Performance and though it has no damping adjustment the novel 'preload' handle works well in the three settings. At about 90kilos all wet I often use the middle setting...too soft, Goldilocks, on the bottom rung and too hard, Papa bear, unless your pillion's a big bottomed girl, on the top rung. The lever basically allows for or limits travel as the method of 'tightening' the spring. Update: Perhaps you know this already since it's a rebuilt shock - I've just re-read your initial post!
Good luck.
How to replace rear Shock on an 85K100RT, Advise please Thu Jul 21, 2011 12:10 pm
