Welcome to OpenCarry.org.
Sounds like you're in a bit of a hurry. I would have to say that you should probably ease up and slow down a bit. You really need to research, read and do your best to understand your state and local laws before you go out and do anything.
For example, it sounds like you do not have a concealed carry permit from MI, or a resident permit from any of the other 49 states. If you don't have a concealed carry permit, you need to be aware, for example, that you can't carry openly while in your car, unless you have such a permit. You can carry openly in the grocery store that sells alcohol, but not in your car. This probably creates the silly requirement that you drive unarmed, with your unloaded firearm secured in accordance with MI law (whatever that is), park, exit, load and openly carry. Then do the reverse after you finish shopping. All without attracting any attention while handling the gun loading and unloading. Pretty stupid in my opinion.
Check out the link on this site to Michigan:
http://www.opencarry.org/mi.html
You can also begin some research here:
http://handgunlaw.us/
Look for the Michigan page.
My advice: If you're not sure you're legal, don't do it. Take the time to do your homework and, if necessary, consult an attorney *familiar* with your gun laws, and even then, question and verify what he/she tells you. Police aren't generally familiar with all of the nuances of gun laws, and often enforce what "feels right" or what they think or want the law to be, not what the law really is. If you get hassled by police, you need to be understand the law and be able to talk intelligently if police try to tell you otherwise. Same with lawyers. Unless they practice and represent people in gun law cases, they aren't likely to be familiar with gun law.