Bruce, that looks like it won't break anytime soon. I will like to see the finished product though. As to stainless hardware, Lowes has an excellent selection and Ny-Lock nuts too. How thick was the plate that you have in the photos? On my website you can see what I did to secure the bar that the hook sets into on page 26 "Center Latch Catch". Since you're doing the latches you might want to do the other part or the catches that are on the bottom of the shell.
Tom
