I have very little in the way of comments in terms of 'being clean' on the road, other than what HoboSquirrel suggested: gas stations, truck stops, places with clean running water and soap are generally able to be found, unless you're *completely* out in the bush...
In which case, there may be lakes! And streams, and rivers, and things of that general nature. I've always been of the mindset that the human body was not meant to be debrided of all naturally occurring bacteria on a daily basis by chemicals made by humans... it's just not natural, I tell you!
But anyways... where in MI are you, and when are you looking to leave? I'm in Muskegon, currently dreaming of leaving it allll behind, again, and going in search of some farm work, hopefully out west. If you're down for a traveling buddy, hit me up...