Here's a pic of the beam and my tentative plan for wing fittings.
I'm considering setting my wings tubing right on top of the beam from outboard edge of the hull to maybe an inch or so past the inboard hull, enough leave space to run a bolt up through the bottom of the beam, leaving a couple inches sticking out the top. Thread a nut down these 2 inches next to the beam. Drill through both sides of the inboard end of the wing, slide the hole over the beam bolt sticking up, washer and nut to secure.
For the outboard fastening point, I'd drill a hole in the top side beam on either side of the wing tubing near the outboard hull. Slide 2 bolts up from inside the beam. Finish by placing a strap across the wing tubing onto the 2 bolts and secure with a couple nuts and washers. Sort of like a U bolt without the bottom part of the U.
A second method would be to replace the existing 2 beam bolts with longer bolts, threaded on both ends. One end into the hull, washer and nut over the top end to secure the beam but with a couple inches of threaded bolt left sticking up. Slide appropriately drilled wing tubing over the top and secure with washers and nuts.
But this last way I'm concerned about putting extra stress on the beam-to-hull bolts in the event of dragging the downside wing in the water. The first way would put the same stress on the beam but would avoid the hull bolts.
Does anybody have an idea of how strong these wing tubing bolts need to be? Most of the designs I've seen look no stronger than either of these methods. I'm concerned about the 3-4' arm created for torque when the wing plunges into the water at 15 knots.
The wing tubing would be parallel to the beam, then bend up just past the outboard bolts at maybe 45 degrees, then bend back to parallel at butt height. No extra smaller support like in the firt guy's pic.
