Disco 2 Radius arm buhes

Hi all
I need to replace the bush in the front radius arm on my Disco 2, the one that goes on the chassis,,,,,,,,,,,,,,,
Is this an easy job, I dont have a press so should i use poly bushes as they are in 2 parts, should I replace all the radius arm bushes, or will changing one be ok.
Where can I get polys to do the radius arms?
any help ?

The disco 2 radius arms are similar to the disco ones? I would certainly use polybushes, but to remove the 2 bushes in the *C* end of the arm, if you haven't got use of a press, then it's best to burn out the rubber in the old bushes (lots of black smoke to upset the neighbours!) in fact once you've got the rubber burning, you can usually push out the inner metal sleeve, now saw through the outer sleeve with a hacksaw trying not to cut into the casting, it can be easier to put 2 saw cuts in at 90º to each other, the sleeve will then just tap out. clean up the hole and you can just push the poly bushes in by hand.