Unscrew ... that's one of the nice things of using screws, easier to change, and reuse ...
Wild birds are generally the critters that carry, and introduce mites ...
1. Remove the roosts in the run.
2. Lower the roosts in the coop to 3'-3.5' high. (Big heavy chickens jumping down too far can hurt themselves)
3. Throw a little scratch or "treat" in the coop when YOU want them to go in, then close the door for the night.
4. Go out after dark, and pick up...