You will need a piece of 3/4 threaded rod, a nut and washer and an old bearing that will fit over the rod. I used an old m/cycle crank bearing. You also need a piece of 3mm plate with a hole in the center for the rod to go through and two holes to bolt to the top of the shock tower. For the bottom part, I cut the base of an old shock of and welded it to the rod. You can make that out of anything, but you have to be able to bolt the lower spring perch to it
Here it is assembled
and the order of it
You feed it all on bar the spring, lower it through the top. Put the pring on and then bolt the perch on
Start winding the top nut till it compessesthe spring enough to line up the saddle bolts. At this stage you can put a jack under the lower arm and bring it up to line the holes up a little easier. Put the nuts on and unwind. tighten up the lower bolts, undo the shock mount bolts and your done.
The bearing at the top makes all the difference, as I tried with out it and the nut kept bindong on the washer. With the bearing it just glides around with no effort.
Cheers