For anyone planning on installing the Ready Brake system on a 2013 Subaru XV Crosstrek, I drilled a pilot hole approximately 1 and 3/8 inches below the bottom edge of the rubber grommet through which the steering column passes. The hole is slightly left of the middle of the grommet. This pilot hole passed through a single-wall firewall and emerged just above a metal conduit on the engine side of the firewall. Much lower than 1 and 3/8 inches in this area and the conduit would likely interfere with installation (or, worse, you might drill through the conduit).
I tried a lower pilot hole to the right (to keep it lined up with the brake peddle) and approximately 3 inches below the grommet and encountered a double firewall. I am going to use the upper location for final installation since it lines up reasonable well with the brake peddle and comes through at a โsweet spotโ on the engine side of the firewall.