Did my 300TDi clutch earlier this year on my own without the use of a crane etc.
This wasn't my original intention, I was going to borrow a crane and lift the gearbox out but at the last minute the use of the crane fell through so I thought I would just do it manually (I had done my S111 the same way many years ago).
Seatbox etc off, removed the exhaust & ancillaries and just pulled the gear & transfer boxes back in one lump and lowered them to the floor. They are really heavy in that state so I split them (replaced the seals at the same time) and re-fitted them manually one at a time. I didn't bother trying to lift them with a jack or anything but just lifted them, located the correct position and slid forward.
Don't get me wrong, they are heavy and it is not for the faint hearted but as I wanted to do the work that day I had no other option. Probably wouldn't choose to do it that way if I had to do it again but it is perfectly possible to do it manually single handed.