I originally did not read your question right.
and gave torque settings for injector bolts ...so deleted post and wrote "wrong answer" just case you had seen the first answer
The manual does not state what torques, the injector component parts, should be . and gives pictures , cross sections ..but no actual strip down or rebuild information
TDDI - what it often says
Have the fuel injectors checked by an
appropriate fuel injection specialist agent.
CLEAN the fuel injectors or INSTALL a new set
of injectors as required only after the specialist
agent checks have been carried out.
So my advice if you want more detailed info
Research: make and model of injector on google ..with the word overhaul or rebuild etc
There is a chance that i missed it or missed the rebuild section ..manuals of late ..are 3 - 4 thousand page PDF files and very difficult to search through or find the right info example "injector ..finds 100's of results in manual "injector torque" --- finds nothing
Will have a good look through the land drover defender 2.4 manual tonight to see if its any different..
BTW there is a whole series of Haynes manuals ..hardback paper books on diesel engines . they may give more detailed info, than the very poor vehicle specific ones .
Note; it's important to read post answers within hours of posting of an answer and pursue it ..as people loose interest ..or forget what its about, or get confused, .continuity stops. or worse your post disappears off the first page and you cant find it.
all the best.mark