Button.

In this case I used 1.2mm sheet aluminium which I sourced from e-bay. I don't know any more about the spec than that, but 1.2mm is easy to shape, even for a novice like me. That was November 2013.

The GDI cover which I made in 2016 is here:
http://www.talkmorgan.com/ubbthreads.php/topics/391495/2

I think the two long brackets were 1.5mm aluminium.

DaveW
'05 Red Roadster S1
'16 Yellow (Not the only) Narrow AR GDI Plus 4