I made mounts for the bimini out of a plastic chopping board and fixed a short ss rail to each one. The mounts are strapped to strap eyes secured to the deck. The rail is then secured to the tubes with bungees around the grab handles. fore and aft support straps are clipped to the grab lines. I can fold it forward or remove it in about 10 mins. Looks flimsy but has worked so far at speeds up to 25 knots. Pics below.
Running around like a head with it's chicken cut off.