It is a fallacy that you only have to be 17 to move out in Missouri. There is a quirk in the law that makes it more difficult for the cops to bring you home unwillingly but make no mistake, if the parents want a 17 year old home badly enough, that 17 year old will be at home. Even in Missouri.
If your parents give you permission to move out at 17, you can. If they don't, you can't. Missouri laws mean zip when you're in Kansas (and, as indicated above, they don't say what you think they say) and crossing state lines without permission does not put you under the jurisdiction of the new state.
All 17 year olds fight with their parents. You're no different. Stick it out another year - you'll have more than enough time in your life for paying bills and wondering where the rent money is going to come from. Enjoy not having to do so as long as you can.