The sensor assembly preferably includes a U shaped support bracket centered about the elongated opening and {HEAD ~ a pair} of sensor block members secured to the support bracket in {TAIL ~ facing relation} 
secured in
The sensor assembly preferably includes a U shaped support bracket centered about the elongated opening and { HEAD ~ a pair } of sensor block members secured to the support bracket in { TAIL ~ facing relation }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL