Do you have what I call clutter in the run? A picture would really help us help you.
But many people have a wide open rectangle, whereas a every chicken can see every other chicken 100% of the time. If you add a lot of stuff, ladders, roosts, platforms where a bird can get on top or underneath. If you set up mini walls, where a bird can step behind. If you set up feed dishes in these corners, where a bird eating at one dish, cannot see a bird eating at another dish, it makes use of the third dimension of space, the vertical, it makes it much more interesting to your birds. And it helps birds get along.
What I would do, is re-arrange the clutter if you have it, or add quite a bit if you don't. Then I would let the girls out of the set up, and lock the rooster into the set up and feed along fence. Then, let the girls in, very close to dark, where the urge to roost is about as strong as the urge to fight. If you can set up a roost, away from where the girls roost in the coop, and lower that will be helpful, I have an old saw horse set up in mine.
This is my go to for integration, it lets the new bird get comfortable in the set up, without being chased and harassed. It seems to let the older birds see the new one in the set up and the sky does not fall.
What I think will happen, is he will roost lower for about 2 weeks, and then they will all fall in love with him.
Mrs K
oh, I missed the part where you want him to move on.