Then {HEAD ~ the skid plate} is supported upon {TAIL ~ the ground} and is manually freely moved relative to the mounting plate until its ground engaging surface is leveled and aligned with the snow plow blade ground engaging edge and the closely adjacent plates form an acute angle 
is supported upon
Then { HEAD ~ the skid plate } is supported upon { TAIL ~ the ground } and is manually freely moved relative to the mounting plate until its ground engaging surface is leveled and aligned with the snow plow blade ground engaging edge and the closely adjacent plates form an acute angle
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH