the thrust receiving flange is held by {HEAD ~ a locknut} screwed into {TAIL ~ an inner peripheral surface} of the second housing through the second housing opening, 
screwed into
the thrust receiving flange is held by { HEAD ~ a locknut } screwed into { TAIL ~ an inner peripheral surface } of the second housing through the second housing opening ,
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH