Place strainer inside a mixing bowl. Pour pineapple slices into strainer; drain. Combine 1 tablespoon of pineapple juice with mayonnaise, mustard, green onion, and cayenne. Spread over one side of each slice of bread. Lay four slices of bread flat on counter. Layer the ham, cheese, pineapple, lettuce, and remaining bread slices. Place on cutting board. Cut sandwiches in half on the diagonal and serv