The tail assembly would become sturdier if there is a support from the buttom upward. And here is he solution. It's the same kind of aluminum, 2 mm thick. Cut and filed by manual tools.

I have nothing but an old vise to use for bending. But the trick is; first make a groove around (0.5 mm) on the plate where you want to bend with a dremel cutting disc, and then bend it slowly. Before bending, I made some brushing with 240 grit sand paper. I'm very happy with the result, it's just great, isn't it?