Find Abigail in camp who will inform you that Hosea is looking for Arthur. Head over to him to begin the mission, his plan is to return the Moonshine to the Braithwaites for a reward. Ride with Hosea to the Braithwaite Manor and park in front to obtain your reward along with another task. Ride the wagon back to Rhodes and park the wagon at the saloon, picking up a crate of the moonshine as you enter the saloon and go behind the bar. Follow the onscreen instructions to begin pouring drinks for the local populace until night arrives and the Lemyone Raiders attack.
You’ll need to be precise with your shooting here if you wish to obtain the Gold Medal. Stick behind the bar and use Dead Eye to score at least five headshots on the Raiders in the saloon, you’ll find four downstairs while another two will shoot from above. Head up to Hosea when he calls to you and you’ll have to deal with one that has grabbed Hosea along with one behind you. Finally, as you approach the doors, two more come crashing through, take them out and jump to the wagon below.
You’ll now need to make your escape, you’ll be constantly pursued by Raiders and you’ll need to be careful. Your accuracy needs to remain around 90% and there’s a lot of enemies to dispatch. Wait for them to get closer to increase your accuracy and use Dead Eye if you’re able to, using Chewing Tobacco or Snake Oil will help a lot here. Once you eventually lose them, Hosea will pull over and let you off the wagon to complete the mission.