Hi Buxto, know how you feel. Just bought a M reg Disco 300tdi auto. Fork out £350 for a cam belt change then got hit with another £450 for a cylinder head jasket. However, that said I've just finished rebuilding pretty much the entire underside of the wagon, all the bushes, all the seals, fluids, pads and discs, lower link assy's. You name it and I've changed it. Generally the work is not overcomplicated. It's good solid agricultural engineering. Don't be frightened to hit it with a hammer (nylon ended obviously). My one bit of advice is, if you're going to remove any bolts etc give them a damn good soak in WD40 before hand. Mine had been in for 18years and were quite determined they weren't coming out. A good purchase is a little kit for extracting rounded head nuts. These can be bought on flea-bay for around £20. All in, the spares I've replaced probably cost no more than about £250 but I've saved myself well over a grand in labour costs. And it's bloody good fun!
Lovin' me Landie