cheers for the reply, the driveshaft ones did leak when i first built it and ive replaced them. the puddle of oil under the car was about the size of a saucer and i was only in there 2 minutes so it must be a big leak as the bottom of the box etc are all covered.

ive checked the engine oil and the level doesnt seem to have dropped on the dipstick

someone mentioned on the xr2 forum that the seal for the input shaft could be on the 'other' side of the box meaning the box has to come to bits to do it.