Riveted nutplates to the sides of the roll bar support. I like the look of these gold rivets in the black paint. These are here in case I want to attach some headset hanger brackets in the future.

Five coats of wax total on the mold. This is from a recommendation of someone on Reddit who builds boats.

Riveted on these nutplates onto the battery box side brackets.

...then realized the presence of the nutplates was going to make it hard to rivet the brackets to the battery box. So, I drilled three of the four nutplates back off. Sigh.

Battery box is all riveted and ready to attach to the firewall.