The mounting brackets 1A, 1B are temporarily held in position by friction provoked by the resiliency of the flexible tongues and {HEAD ~ arms} helped by {TAIL ~ the relevant first, second, third and fourth detent projections} 71, 73, 75 and 77 
helped by
The mounting brackets 1A , 1B are temporarily held in position by friction provoked by the resiliency of the flexible tongues and { HEAD ~ arms } helped by { TAIL ~ the relevant first , second , third and fourth detent projections } 71 , 73 , 75 and 77
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH