Yes and you really need the boat off the trailer. I just made them at home then took everything I needed to the river with me one day and swapped them out in the parking lot near the launch. Battery drill driver was great.
On my old runabout I just lifted one side at a time off the bunk with a floor jack and some 2x10's. Switched old for new and let her back down. Didn't want to try to lift a Moomba that way though.