I'm looking to find a shock with preload adjustment. Doesn't need to be anything special. Its fine if it needs a rebuild.
I have a Koni 2615 in pretty good shape. It is damping adjustable, but not for preload (other than by shims). Fits all 2V K's. Works perfectly for my 190 pound self, wearing full gear and a bit of luggage. Works out to 220# total load how I normally ride. Smooth and stable. However, when I travel or take my GF as pillion, its way under preloaded.
Its perfect for a bike setup for one job. Shim it in to perfect, and ride the piss out of it.
Willing to trade +/- money on either side too.