The top wall also includes {HEAD ~ a unitary mounting wall} extending downwardly from {TAIL ~ the outer peripheral edge} of the top wall 
extending downwardly from
The top wall also includes { HEAD ~ a unitary mounting wall } extending downwardly from { TAIL ~ the outer peripheral edge } of the top wall
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH