ohh piss easy. take the seat off, and you got two bolts. its a bit of a squeeze to get in there, and thats because of the rubber swingarm mount bushes, they are rubbish. I am going to get the Alls Balls bearing kit for them. also you might need to shim the gap where the shock mounts are, just a couple of mild steel washers will be fine, will allow you to really reef up the bolts without squeezing the mounts. but you may not need to. if you dont understand what i mean now, you will when you install it.
would also suggest sliding your axle back as far as you can, just to get some extra length in the wheelbase, with the longer shock you really mess with the geometry of that little swingarm. originally i thought I was going to be ok with the stocker, but i can see the benefit in a +1 or +2 swinger now. Might even drag out the welder and fab something myself. wait and see how the new shock goes.