If it will be chill in the car, you can use a cooler instead of a box(still with newspaper cushioning) and you can also use a hot water bottle(put in the cooler, but not on the snake), and refill the hot water when you stop somewhere if necessary.
5 hours is a short trip compared to shipping him, so he shoudl be fine. Just like the above post, leave him in his new dogs for a week, no handling to relax.