Once positioned adjacent the boat, {HEAD ~ the mobile boat supports} are anchored to {TAIL ~ the deck} and a boat support structure is extended from the mobile boat supports to engage and support the boat 
are anchored to
Once positioned adjacent the boat , { HEAD ~ the mobile boat supports } are anchored to { TAIL ~ the deck } and a boat support structure is extended from the mobile boat supports to engage and support the boat
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH