{HEAD ~ The retainer} is inserted into the retainer insertion hole and held in {TAIL ~ a temporarily secured position} 
is held in
{ HEAD ~ The retainer } is inserted into the retainer insertion hole and held in { TAIL ~ a temporarily secured position }
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL