I haven't seen one with pictures - but here's a recent one done for a 722.1 transmission - for removal of the 722.3(?) transmission in your car it is very close to being the same.
http://www.peachparts.com/shopforum/diesel-discussion/307756-722-118-transmission-removal-replacement.html
Some people say it is easier to remove the engine and the transmission in one go! And then split the transmission and engine later on. It does sound a bit mad but I imagine it is much easier to remove and fit the transmission. There are some delicate bits that really don't appreciate being shoved, kicked and knocked.
BUT before "we" get round to fitting your 30 quid transmission can you confirm the transmission type you've got? We need a number like 722.3XX which you'll find on the right hand side of the gearbox just above the oil pan (of the gearbox)...
...I'm guessing you're gonna be lucky if you install your 30 quid transmission and not have any trouble. Swapping a transmission is a lot of work only to end up in a similar situation - perhaps it is worthwhile making sure that the old one is shot first?