The graphical information includes {HEAD ~ information} about: {TAIL ~ the necessary optical part} which should be newly installed in the main equipment; and the installed optical part which should be removed from the main equipment 
The graphical information includes { HEAD ~ information } about : { TAIL ~ the necessary optical part } which should be newly installed in the main equipment ; and the installed optical part which should be removed from the main equipment
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH