zooknut

I have got a 1996 ZX TD Leader Estate, the trailing arm bearings on the nearside rear suspension need to be replaced. Are they very difficult to replace? If so is it best to try to get a complete rear axle assembly from a breakers yard, or just get a used trailing arm? Also is the trailing arm and/or rear axle assembly the same on the estate as the hatchback? Thanks in anticipation for advise on this matter.