The rearward section can be moved longitudinally to adjustably locate {HEAD ~ its rearward edge} in {TAIL ~ a selected position} forward of the trailers wheel assembly 
in
The rearward section can be moved longitudinally to adjustably locate { HEAD ~ its rearward edge } in { TAIL ~ a selected position } forward of the trailers wheel assembly
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 OTH OTH OTH OTH OTH OTH