Have a little look through this thread..
http://www.landyzone.co.uk/lz/f10/oil-leak-gearbox-229433.html
And this one if you are bored
http://www.landyzone.co.uk/lz/f10/4-4-2004-clunk-when-taking-up-drive-250674.html
I've had the box out together with the transfer box which weighs similar to a small car and over Christmas i took out the transfer box on its own.
The most difficult part is the weight of the parts.
A very good mechanic friend helped me with the transmission removal and rebuild and i did the TB on my own apart from my neighbour helped put it back in which was a total bar steward without a transmission jack that you can buy for about £100 i realised after.
Without question, if you are doing this on your drive, you will need to raise the vehicle front and back enough to get the transmission out, recently I have done this by driving onto 4 sleepers but that was only to get the TB out, but you need considerable height to get the trasnmission out. we actually built some full length ramps.
Forget 4 axle stands ! The second issue is the amount of height you need to get the box out is the height you need to be able to raise the transmission to get it back in which sounds obvious and what might help would be to be able to raise and lower the vehicle.
Its probably easier to put the TB back on the transmission first but what goes against you is the weight and to be honest providing you have some decent extensions bolting the TB back on with the transmission that's already in ins't as bad as it would seem. The two bolts that you can access easier are the two at the very top, all the others are almost impossible to get anything other than the ring end of a 10mm spanner and an extension tube.
Honestly, i spoke to an auto box specialist who was going to charge me £1200 to remove the transmission, replace the torque converter and strip and rebuild the box and if you are not confident in doing it yourself, have a fair few tools and plenty of time, i would probably get it done at a garage, but make sure they use the correct oil for the rebuild.