Terry,
Thanks! I used "hard action" snap sockets, which are harder to unsnap and riveted a cloth-to-cloth standard stud to an alloy tube. I sewed a length of polyester webbing on the tail of the top for reinforcement and attached the buttons and snap sockets thru the canvas and webbing. So far, no problems at 90 KPH. But it does flap a lot at speed.
I got the fabric and fittings from Sailrite.com. Prices were very reasonable.
Jon