We have had recurrent damage to our keel when transporting, including on delivery. We followed the dealer's instructions to the letter. Recently, we repaired the keel for the fifth time. I called JBoats and they gave us a procedure that is very different from what we were told initially.
First, after putting the boat on the trailer, leave the keel suspended while strapping the boat down to the trailer. Next, place 6" wide by 0.031" thick nylon sheeting(http://www.mcmaster.com/#orders/=uz8rcb) along both sides and the front of the keel, moving it side to side to allow the sheeting to move into place. Use a piece of split hose to protect the trailing edge. Tape the sheets in place and lower the keel. Put the wedges in place. Strap the keel down and back. They recommend covering the keel to prevent road debris from entering the keel box.
They tell me that they have had no damage to their keels since using this procedure.
Bruce McDonald #50
Austin, TX fleet 14