Hi Paul, do you mean a stainless u-bolt? Installed one that has a rubber deck protector around the bolt on a kayak. Installed it after the endpour was in. masked deck, drilled hole oversize,mixed up poxy with high density filler(wood flour would probably be fine),pushed u-bolt in,cleaned up mess,turned boat over onto u-bolt since the rubber protector has a metal plate in it that is compressed between notches on bolt and deck. If you don't have a rudder something like this is great in the stern for tipping the boat on end to get water out.