Nick, assuming we're talking about the bushing that is in the bottom of the rear wheel carrier:
1- It will look something like the photo at this URL:
http://www.SamstagSales.com/SirTool/stm_0085.htm
2- I believe the proper tool will both remove and install the bushings. If not, you should be able to beat the old one out with an air hammer or something similar.
3- Never use rope to tie up an MB coil spring unless your life insurance is paid up and you don't mind the possibility of getting killed. Treat compressed coil springs like a grenade with the pin pulled. Either rent the proper MB spring compressor, or you may be able to remove it with a couple of good hydraulic jacks (REAR ONLY).
4- Inspect all the other links carefully and replace anything else that's worn, while you're working back there.