grasping {HEAD ~ the carpet} to be installed at {TAIL ~ a given distance} from said wall edge 
to be installed at
grasping { HEAD ~ the carpet } to be installed at { TAIL ~ a given distance } from said wall edge
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH