You'll be in my neck of the woods. We're about 40 miles NW of the Mac Bridge.
Yes, you can drive on the sides of the roads as long as it isn't an M-road (state highway) or interstate (I-75 is our only interstate). There are a few other local restrictions but they are few and far between UP here. I typically stay away from federal lands, they aren't as open as the state forests. It's quite easy in my area to ride all day, 100 miles + and never hit the same trail twice. If you ever want to come UP with your buggy send me a message, I'd be glad to show you around.
The area circled is pretty much open unless posted closed, there is quite a bit of Federal forests on either side that can be used but trails are severely restricted compared to state owned/managed lands.
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