Don't for get there's around £80 in bearings and oil seal, you will need markers blue or similar, might need a set of shims £20 ish from ascroft I think, you will need a puller to remove the old bearings from the pinion, a press to press the new ones in the diff case on to the pinion and the carrier bearings,you will me a good quality dti gauge to check the run out on the crown wheel and for setting the backlash, the appropriate tool for checking the preload, ideally a hight block to check the pinion hight. You will have to drill and tap the diff case and form the airline for the inside and flare it.
Oh and lots of cleaner to get rid of the oil as it gets every where.