When Joey and Charlie are sitting in the back of Pacey's car, different camera angles show Charlie's arm around Joey from his side of the car, but from her side, it's down by his side.
Charlie claims the drive is 6 hours but Massachusetts can be crossed in less than 4 hours. The group is driving from Boston to near Salem - about a 45-minute drive (assuming they reference Salem, MA due to Pacey's comment to Audrey). Since they will be about 30 minutes from Salem, it would unlikely to be more than a 90-minute ride with heavy traffic.