after converting my petrol 90 to tdi from my rotten disco just got round to fitting transfer box.
after fitting and driving for a couple of days noticed bad oil leek on ground defo from transfer box as its gear oil not atf. so put it down to me catching input oil seal when fitting box took it back out today and seal looks perfect cant tell if leeks from input seal or from rear of intermediate shaft .any body had box to bits to fit new o ring if so is it a bad job
cheers in advance for any help

More likely the O ring leaking on the shaft - look here for the manual
pdf Land Rover Manuals | Landroverweb.com