Clutch replacement

The clutch on my 993 has started slipping. I've never done a clutch before but I understand the gist is:
- prop shaft off
- gearbox off
- clutch is now accessible

Is there anything special I need to know? Or any special tools I'll need? And anything I should look out for when buying the replacement clutch?

Buy a decent branded clutch, don't go for a cheap brand you have never heard of as they are very hit and miss. I tend to drain the gearbox oil but I don't know if that is necessary on these (I've only done front wheel drives where the drive shafts actually go into the box) A clutch alignment tool is handy but not crucial, some clutches come with one. Make sure your new clutch is the complete kit with the release bearing too as you might aswell change the lot whilst you have the box off.

Agreed as above although it is possible to improvise a clutch alignment tool if you have a good selection of sockets and don't skimp on the clutch release bearing you will regret not changing it if it gives up and you have to have it all apart again and take a little emery cloth to the flywheel if it looks shiney and check it is flat too while you are there.

Update on this in case anyone is interested:

I've been driving around a bit more carefully lately and can pretty much avoid slippage entirely so long as I don't floor it going up hills. This is fortunate as I'm fairly busy with university at the moment. I'm doing the Mongol Rally (unfortunately not in the Hijet) from mid-July 'til about September so unless there is catastrophic failure I don't plan to touch the clutch until after I get back.

The advice here is well appreciated and will be useful when I come around to doing the job!