There are multiple hits for the lower shock mount and (most) rear disc brake installs.
Either the lower mount needs to be relocated (usually just moved inboard a smidge), or some just create a new shock bolt location. Moves the lower shock eye to the inner flange wall of the mount.
Another way that is successful sometimes, is to mount the shock shaft to the lower mount and the body to the upper. This often gives enough clearance because it's the shock body that usually hits the brake caliper.
Some shocks, some particular Bilstein 5100's for example, mount this way on purpose. Easy peasy win win in that case.
Mounting the shock eye inboard of the mount, using either a longer bolt to act as a stud, or by simply bolting it to the mount wall, seems the least desirable. It puts the shock mount in single-shear, rather than the factory's more desirable double-shear mounting.
But it's quick! Don't know that I've seen more than just a couple done this way, but don't know that I've ever heard of them having trouble either. Personally though, I would not mount one in single-shear and expect it to live a long life if you have stiff shocks (heavy valving OR strong gas charge for example) or work the suspension hard.
The 100% cure is to relocate the shock mounts. But only do it if you need to.
Paul