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