I guess it depends on how you want to travel. A fast trip just to get to Eureka, then I-40 to I-44 would be the best route. But, if you want to sight see and take your time, then pull out the map and check out some good spots. Also, you might want to look at doing the Route 66 Alignment. Lots of nice things to see on RT. 66 and it goes from So. Cal, all the way to Chicago. (but you can stop at Eureka on 66). Enjoy your trip!