These are all good points. What i am afraid of is i will not be able to use this mast and have to buy another one. Not really the end of the world but kinda like to know heading into it. The old mast has all the hardware. so eather way i would be able to just buy the extrusion. If I could setup the furlling maybe I should go that route from the beginning. i like the idea of a furlling main.
Just thinking outside the box.
But if you could close up the big opening somehow and mount a Tides Strong Track on whatever you used to close the gap. You would pretty much have a conventional mast.
I doubt that welding would be an option, but perhaps aluminum flat stock could be inserted into the cavity and riveted to the inside of each edge of the opening. The Strong Track could be attached to the flat stock.
Just a thought.