It is all in there, checking components, replacing lining etc - what more do you need?
eg:
Visual inspection of glow plug lining
Carry out step 5.4.1 to step 5.4.3.
After removing the glow plug, check the lining in the socket for
dirt.
– Normal soiling of the surface: Use suitable agents to clean lining.
– Heavy soiling of the surface: Replace glow plug lining, see
step 5.5.2
Note!
A highly soiled lining can only be removed destructively. On removing,
ensure that no dirt or parts of the braiding fall into and block
the fuel line. After removing the lining, clean the glow plug sockets.