inserting a lead of a component into the plated through hole so as to position the component on {HEAD ~ the first side} of {TAIL ~ the circuit board}; and then 
of
inserting a lead of a component into the plated through hole so as to position the component on { HEAD ~ the first side } of { TAIL ~ the circuit board } ; and then
OTH OTH OTH OTH OTH OTH OTH OTH 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