Even if you decide to hand wash in bathtub in cool water, I would still put in several of the Shout color catchers, just to be safer. I have washed a few of my antique quilts in the bathtub and then dried outside, exactly as Prism described. I would also suggest that you have someone to help you with the washing process as the quilts become unbelievably heavy after they are in water. Unless I'm unbelievably weak
. One of the antique quilts had a dark brown fabric that ran and that was the one I washed by myself. I really think if I could have handled rinsing it more, it might have rinsed out, but that was not the case. Color Catchers weren't around yet when I did the handwashing but I always use them when machine washing my quilts now.
By the way, that is a beautiful quilt! Hope all goes well for you.