Meanwhile, if you work on old Landrovers from the Defender 90/110 to early RR L322, you need this:
https://rangerovers.pub/downloads/rave.zip (500MB zip, PDFs of all service and user manuals).
Even if you don't work on them, grab yourself a copy. You never know when you might need to know how to rebuild a Borg Warner transfer box or ZF 4HP24 gearbox.