hi robert it is a reasonable straight forward task, did it recently on my herald.
You need to mark the prop shaft first while on the car so it goes back on the same way (score both bits of the flanges) keeps the thing in balance.
your going to need two replacement uj's with grease nipples
jack
axel stands
spanners to undoo the propshaft bolts (you may want to replace the nylock bots and nuts)
A soft faced hammer
metal vice (didn't have one at the start but really needed one)
old socket to drift the new uj's in
circlip plyers
perseverence and time if you haven't done it before (it took a while to get the old uj's out)
the hanynes manual is good and the link below from Bill is really helpful too, same principal although his artical is about half shafts.
http://www.rarebits4classics.co.uk/Hintsandtips.ht...
If all else fails the local prop shaft balancing place oftered to do the whole job and balance the shaft for £80
Hope this helps
Regards
Aaron