In my experience, monti-cap can do well in a pretty wide range of lighting. I wouldn't worry too much about the area that's shadowed. As it grows outward, you can trim it back and it will grow upward toward the light, creating some pretty cool patterns.
Going to add a rock and place it flat here to keep it lower. Thanks for the suggestions, I post when I move it. Will adding a few pound dead rock cause big issues ?