These started life about a century ago as horse harnesses , I removed a lot of tabs & various gizmos and took a good bit off the surface to get past the rust pits. It took a bit, but the shape and inside webbing is so perfect, They were an awesome find.
Rough cut after removing stuff..
The left side I over engineered the brake stay mount and left some of the original casting web on either side.
Ill make a matching sleeve at the joing in front of it to mach rear, and duplicate on the right side, for a way back when look.
The inside of the is very neat, & a good way to run tail light wires and speedo cable.
The right side.
And the cat was so glad I was back working he of course would not get off my shoulder while I worked. Freak.