The few steel adapters that I have held in my hand were 10mm plus in thickness. They were also made from high strength steel alloy, not mild. I am pretty confident that he guy who designed these probably has no idea what grade steel they are. How do you make strength calculations to verify if they are strong enough without even knowing the build material. Also, due to the massive 1" spacer required the brackets would need to be even thicker than normal to help make up for the additional leverage the caliper is now going to exert on them. Not to mention the fact that the requirement of a spacer is going to add a second joint where the mounting hardware could potentially be put under sheer stress. This is bad as the hardware isn't designed to be loaded in sheer and is not nearly as strong this way. Any other issues I didn't address that you can think of?