The graphical information may be: graphical indication of the installation locations of {TAIL ~ the optical parts}; different pictorial expressions about the installation and {HEAD ~ the removal} works; and graphical indication of the identification marks of the optical parts 
The graphical information may be : graphical indication of the installation locations of { TAIL ~ the optical parts } ; different pictorial expressions about the installation and { HEAD ~ the removal } works ; and graphical indication of the identification marks of the optical parts
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH