I had anticipated that boarding might be an issue and had purchased a small but sturdy aluminum two step ladder, but it did not really meet the need. The orientation parallel to the boat made it clumsy to reach the ladder as the "A" frame placed the steps too far away, and placing the ladder perpendicular did not seem stable enough.
Using the rub rail as a step was a possibility--like the picture below. I had used this "method" of boarding (without the teak tread) as my personal boarding step. But it seemed to small (not deep enough).
I considered aluminum, but the material was just too expensive and I would need to hire a professional to TIG weld it.
I cut the pieces with a circular saw and a jig saw. Used a 4 inch grinder, a Dremel grinder and oribital sander to shape and finish. I used a router to cut grooves for the joints and assembled with screws and epoxy. Since it was pine, I added reinforcement to the sides and the tread, making them 1 1/2 inches thick.
To fit the unit to the boat, I actually whittled with a knife to get a precise fit--the goal being for the weight to be shared by the gunwale and the rub rail...and "torque" to be shared by the gunwale and the hull below the rub rail.
I then painted with white automotive lacquer and caulked the joints/cracks. Finally, added two aluminum strips to the step tread for traction. Below is a pic with a t-square adjacent to allow a sense of dimensions.
For some, a one or two step stool will be a welcome addition. For more agile passengers and crew, this step should be enough. One foot on dock, the other on step, left hand on boat railing, right hand on flybridge step bar as you step over gunwale. Below is a pic of the final setup.