how do i get the filter off on gearbox? iv took the bolts out and its come loose. but the subframe is in the way. any ideas how to get it out? thanks

One of our wonderful mods might want to move this to the right section.

But the thread linked here thread might help point the OP in the right direction with his problem:
http://www.rrsport.co.uk/forum/topic29953.html?highlight=wrestle 2008 MY Java Black TDV8 HSE

I did it on my TDV8 which is similar.
undo the 21 oil pan bolts and cut the oil suction pipe.
you can not install a new plastic pan but you have to install a steel replacement pan instead.

first fit the new separate oil filter, slide new steel pan in and put new slightly shorter bolts in.

that's it.

iv bought the replacement part from land rover so it has suction pipe on and cant get the new one in as subframe in the way

Well, then you have to release the right engine mount and jack the engine up to get clear access.
this way must be possible but I did not take that risk and went for the steel pan instead.

The official Land Rover way of doing it says remove the transmission support crossmember. There is a pdf version of the Disco 3 manual on this link (first item on the list) and you need Section 502-02.
http://www.rrsport.co.uk/forum/topic28424.html

Basically seems to say support the transfer case and unbolt the crossmember and disconnect part of the RH exhaust. 2008 MY Java Black TDV8 HSE

Undo RH engine mount, transmission crossmember, and jack the whole.lot up as high as it will go.

Takes a bit of maneuvering to get it out and back in, but there is just enough space