not sure exactly what you are asking ? do you want to disassembly an already removed injector or remove one from the engine why is the extractor needed?
Note if this is a common rail injection system I would not be doing anything to it as the extremely high pressures these CRD systems run at can kill - it can slice through bare skin & clothing like butter !
I do have a WSM PDF for the early Sprinters I can upload to an FTP server.
Cheers
Wombat13
December 2013