Second configuration signal device assembly 20 differs from the first configuration only by hook 60 being formed on the front end of {HEAD ~ rod} 58 instead of {TAIL ~ a straight front end rod} 48 
instead of
Second configuration signal device assembly 20 differs from the first configuration only by hook 60 being formed on the front end of { HEAD ~ rod } 58 instead of { TAIL ~ a straight front end rod } 48
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 OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH