The crusher replaces the drilling machine upon {HEAD ~ completion} of the drilling of a guide hole by {TAIL ~ the drilling machine} 
by
The crusher replaces the drilling machine upon { HEAD ~ completion } of the drilling of a guide hole by { TAIL ~ the drilling machine }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL