Land Rover Repair: 2002 td5 disco TD5 Rear Half shafts, rear bearings, rear hub

Question
i need some help with a 2002 td5 disco TD5 Rear Half shafts i can not undo the 32mm nut in the center of the disc,
PS sorry i was mixed up over the rear disc's,ive put new disc's on the rear but i have this rumbling noise when driving [ the noise was there with the old disc as well] , so thats why i need to check the rear bearings ,and when the 32mm nuts are off how tight do i do them up ? also what need to change the rear halfshaf bearings?

Answer
There is nothing to "check" in the rear hub bearings on a DII.  They are expensive sealed units that are either replaced whole or left alone.

There are no separate halfshaft bearings.  Older Land Rovers had full floating axles but the DII models do not.