In the picture below you will note that the rotor’s OD is parallel with the edge of the parking brake’s pad. This leaves approximately 1/8” between the rotor’s OD and the caliper’s ID. You will also note that the caliper isn’t exactly centered on the caliper pin (or whatever it’s called).
The following picture shows an outline of the bracket and where and how deep the threaded holes will go to achieve 2x screw diameter (i.e., 20 mm).
The next step is to wire it up and test it. Apparently you need both calipers plugged into the ECU for it work.