I've been on parts -- it's pretty cool for a little while but I can't even imagine doing the entire stretch. Good luck! A few places to hit:

Wigwams in Holbrook, AZ -- definitely stay overnight here
Joe & Aggie's Cafe in Holbrook, AZ -- have a meal here
Ted Drew's Frozen Custard in St. Louis (pick up some doughnuts at the shops around here as well)
Ariston Cafe, Litchfield, IL -- have a meal here