The two end plates 514 each include {HEAD ~ an opening} 518 into {TAIL ~ the passage} 516 
into
The two end plates 514 each include { HEAD ~ an opening } 518 into { TAIL ~ the passage } 516
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH