If you web search "STP Camping" you'll see options to pre-register for camping at various locations. Put your bag on the truck going to wherever you are going to stop and then enjoy the ride. None of the hills are that bad, just grind up them. I've only done 1 day STP's, but if I was going to do a 2 day, I would go furter than Centralia on day 1. Get as many miles knocked out as you can the first day, cause it's going to be hard to get back on your bike day 2...