After describing how to do this in another thread, I remembered I took some photos when I did mine so thought I may as well stick em on here in case it helps anyone out when they come to do theirs! Checked the how to thread but there's nothing for suspension!
Removal: (car on stands) Remove rear brake disc and caliper and move the heatshield out of the way for access. Unbolt the trailing arm from the hub. Drill through the rubber of the hub bush in a few places until you can push the inner sleeve out and take most of the rubber with it. Clean an area at the bottom so you can see the metal sleeve. Invert a hacksaw blade in the frame (feed it through the hole first) and cut through the sleeve (be careful to stop as you reach the "breakthrough" point). Knock a screwdriver into the gap and lever the sleeve around til it comes out. Clean up the hole.
New poly ones: Grease the hole in the hub. Grease the leading edge of the new sleeve and knock it lightly into place with a lump hammer and block of wood (do NOT damage the sleeve). Using a 32mm socket, long bolt, large washers (existing: from the hub bush assy) and nut, drive the sleeve into the hole. Then add a 27mm socket (might have been 24mm) to the "driver" assembly and use it to help fit the two halves of the bush. push the inner sleeve home and you're done.
USE THE GREASE from the kit for all parts - sleeve to hole, bush to sleeve, inner sleeve to bush.
Just gotta put it all back together then!
The placcy washers go one each side on re-assembly then the metal ones outside.
Hope it proves useful to someone!