Disco 2 Replacement turbo cartridge

Okay, I've decided, as I love my D2 and want to keep her on the road and relatively trouble free for as long as possible, I'm embarking on a round of preventative maintenance. One of the jobs on my list is to fit a new turbo cartridge as there is oil leaking into the pipe to the intercooler. There is also a very slight amount of play in the bearings. Considering the car has done nearly 200,000 miles I think it's time.
Anyway, my question is... has anyone done this job and how did you find it? Did it go well and was it difficult? Also, there are lots of cartridges on the market and the prices vary dramatically. Which cartridges do any of you recommend?
As always any advice gratefully received.

I've done it on my 300tdi 90 and a Vauxhall astra 1.7, probably will do it on my td5 eventually,. I used turborebuilds on both, recommend them 100%. As for fitting I would suggest drenching the bolts on the turbo cartridge in plus gas or some penetrating fluid (not wd40), and mark the manifold where the oil hose is so you get the cartridge in the correct position

I did my D2. Easy job on the bench just keep everything sterile. I cannot remember which cartridge but it was from a reputable turbo parts supplier. Seems to run okay.

This is great news guys. I've never done one before. I've seen it done in videos and dealt withe the stuck waste gate issue. I'm thinking the disassembly doesn't look too bad and I'll be sure to mark the manifold for the oil pipe position. I have oxyacetylene in my workshop which seems to come in very handy for those immovable bolts Landies seem to love
I'll look at turborebuilds, I always prefer a recommendation from someone for parts like this. Most things I go for genuine if possible like swivel joints as you don't want to be changing them every 6 months but I'm guessing a turbo blow up is kind of terminal!!!

The worst bit is removing the turbo, as the downpipe nuts can be a swine and shear off. Also the bottom one to the manifold is awkward. Plenty of heat and penetrating oil

I have rebuilt cartridge on mine for about 6-7 years (previous owner has done this). It runs OK (was checked by turbo specialist about 2-3 years ago and confirmed OK) but having oil in the pipe from the beginning.