I need to change the gearbox and transfer case oils on a friend's tdci and am finding conflicting views as to which oils should be used. Could someone please clarify?

I have read that the MT82 box should use a 75w90 GL4 oil (definitely not GL5) on one site but then saw that it should use MTF94 on another site.

As for the transfer case, is 75w90 gl4/5 ok?

The information does take a bit of sifting through to get the right answers.
Transfer box first;
The Land Rover workshop manual (page attached) says 75-90 or 80-90 GL5. The owners handbook says Castrol Syntrax 75W/90 or Texaco Multigear 79W/90 or equivalent. I use Castrol Syntrax Universal Plus which is a full synthetic 75W/90 and meets GL4 and GL5. (I could also use it in the gear box if I choose to). Worthy of note, the filler plug on this model (tdci) is NOT a level plug, you need to measure the volume in.

Now the gear box;
The workshop manual (page attached) says Manual transmission fluid to specification WSD M2 C200 C. (this is a Ford spec). The owners handbook specification says Castrol BOT 130 M or equivalent. (The Castrol web site guides you towards their Syntrans range). Although I would not hesitate to use the Syntrax as in the transfer box, I have found Comma MVMTF Plus which is a fully synthetic 75W/90 GL4 which ticks all the specification boxes. Sheet attached. (Note Castrol do a Syntrax and Syntrans range).

Thank you