According to the invention, {HEAD ~ the means} of fixation of the said tank to {TAIL ~ the said engine unit} are preferably deformable 
to
According to the invention , { HEAD ~ the means } of fixation of the said tank to { TAIL ~ the said engine unit } are preferably deformable
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH