I held off commenting to get a better feel for it and my overall statement is: the basic ones I bought work, but the left one is floppy because there's nothing inside providing rigidity and that causes some problems when wearing gloves. It ends up the right one has enough rigidity with the brake fluid reservoir holding it in just the right place, so the current proposed idea is to 3D print a mount and add something on the inside on the left side only. Ironically, my first thought was to add some mini bark busters on the INSIDE to give it structural rigidity, like a dirigible. Since it just needs to stop it flopping around and hold it off the grips, it probably won't be anything too crazy.
I think you could achieve something pretty close with some mounts, strip metal, and an OJ bottle, but I have a 3D printer and I just don't want to do that kind of mental gymnastics when I have CAD skills.