{HEAD ~ The passageway} includes a fuel delivery end located in a firebox and {TAIL ~ a fuel infeed end} below the plate 
includes
{ HEAD ~ The passageway } includes a fuel delivery end located in a firebox and { TAIL ~ a fuel infeed end } below the plate
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH