I ran 2"X2" rails, one above 6/8 of the windows on the shotgun side, the other at a distance pleasing to my eye beyond the steep curvature where the wall morphs into ceiling.
Used Teks 1/4-14x 2.5" self-tapping screws to attach the rails to the ribs.
Consistently coming off of the same side of the hat-channels, I finagled around, figuring out optimal stud & rafter lengths, and what mitre cuts were needed to get firm fits in all the pocket joints.
Get the image in your mind, and then muck with mock ups til its right. Transpose the measurements, and you're ready to plug n chug!
Those who say that it cannot be done should not interrupt the people doing it.