In a preferred form of the invention, the system includes {HEAD ~ a means} for adjusting {TAIL ~ the tension} of the cable 
for adjusting
In a preferred form of the invention , the system includes { HEAD ~ a means } for adjusting { TAIL ~ the tension } of the cable
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH