I have finished weathering the helmet and all that remains is to install the visor.
The owner sent along a set of metal parts that closely replicate the "clips" used on the original ESB lid.
Here's how I got them ready.
In panel 1 you can see the parts. There are two drilled/tapped blocks with stainless screws, plus two thin metal strips for the upper clips. There are also two drilled/tapped tabs with brass screws for the lower mounts.
In panel 2, I have bent the strips using some needle nose pliers.
Panel 3 shows how the clips will look when installed.
In panel 4 I'm bending the lower tabs so that they'll fit the angle of the cheeks.
Once they're ready I'll use epoxy putty to secure them into the helmet.