I don't know about Cheeseland, but Minnesota only requires one mirror total. I got pulled over for a front plate issue in August and the cop didn't say a word about my full side mirror delete. Also, X2 on having better visibility with the fisheye stick-on mirror. It's amazing.
If any of you are considering removing a mirror entirely I suggest reading the statute first-hand. You may get lucky!
Edit: here we go!
Wisconsin Motor Vehicle Equipment
347.40 Mirrors.
(1) No person shall operate any motor vehicle upon a highway unless such vehicle is equipped with a mirror so located as to reflect to the operator a view of the roadway for a distance of 200 feet to the rear of such vehicle.
So legally, you only need one mirror, which can be your interior rear view mirror. I put a fisheye on mine and it works better than a side mirror.
Michigan, however, only requires one and it has to be on the outside. Oops. Not going to change that until I get pulled over for it.