It's not difficult at all, and doesn't even involve going inside the roo, it literally takes 10 seconds... Most breeders do it. They separate the hens from Roos to keep them in condition and AI them. I let mine stay together but my austrolorps are so big that they can't naturally mount.
They must be huge? Mine are pretty big and we don't have a roo but I can't imagine it being an issue. How much do yours weigh?