I have a 28'' southercross that has about 23" of free board. I saw a boarding
ladder in the west marine catalogue model #584427, around $150. I cut about 1 and 1/2 inches of the end of the
ladder, made two small
u-brackets and fassened them to the top of my gunnal, used a 3"X 1/8" X 17" piece of stainless steel under the brackets to distribute weight. I drilled a hole in the ends of the
ladder about 1" from the end I had cut off. The
ladder swivels from the up position, tied with a slip knot to a life
line, when flipped over the side to the down position it has two steps under water. The whole project cost $155 and 1 hour of work. It is working great as a universal boarding
ladder and is out of the way on the outside of the life
lines.