Before beginning this mission, make sure you have your two best sidearms equipped and that they’re clean, you’ll want to complete this mission using only those weapons. The Gold Medal for this mission is one of the hardest you’ve faced yet as not only will you need to be quick, but also need to score many headshots while not incurring much damage yourself. You may find you need to replay this mission later once you’re more comfortable with the shooting mechanics. You’ll also need to skip cutscenes where possible to save a little more time.
When you’re ready, make your way to Rhodes and meet up with Bill, Micah and Sean to get the ball rolling. Follow the gang slowly down the main street towards the Sheriff’s Office when matters take an unexpected turn (or expected in Arthur’s case). Stick to cover and make use of Dead Eye to start headshotting as many enemies as you can. Of special note are the enemies on the roof of the house to the right of the Sheriff’s Office. You’ll need to fire from all sides, use the cart behind you as cover when you switch to shooting behind you.
Eventually, you’ll have to make a run for the gunsmith so quickly dash around the back and kick the door down to find one enemy taking cover at the window and another to the right with a shotgun. Once both are eliminated, use the window as cover and begin aiming for more headshots, you’ll start encountering mounted enemies at this point so consider using a Snake Oil to make use of Dead Eye more.
Once the enemies retreat, head outside with Micah and make your way back down towards the Sheriff’s Office. Bill has managed to get himself caught and you’ll enter Dead Eye automatically and you must score at least three kills here so aim for their heads and be sure that you target the one holding Bill first. Once the final Greys fall, Bill takes Sean’s body and you get out of there, ending the mission.