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