{HEAD ~ The shim} is then formed to include {TAIL ~ a feature} on its surface which complements the surface profile of the assembly surface 
is formed to include
{ HEAD ~ The shim } is then formed to include { TAIL ~ a feature } on its surface which complements the surface profile of the assembly surface
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH