Said {HEAD ~ speed changing operation} of said either one transmission mechanism started in the step establishes {TAIL ~ a third shift position} in the automatic transmission 
establishes
Said { HEAD ~ speed changing operation } of said either one transmission mechanism started in the step establishes { TAIL ~ a third shift position } in the automatic transmission
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH