The side members are gripped by gripping means to maintain {HEAD ~ the side members} along {TAIL ~ respective straight transverse axes} 
The side members are gripped by gripping means to maintain { HEAD ~ the side members } along { TAIL ~ respective straight transverse axes }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL