Free rustic camping near Lake Michigan
There are plenty of really rustic pull-offs north and south of those coordinates on Green Rd. There are actually quite a few that are harder to find or even get a vehicle to without 4WD, but most of it is easily accessible in a 2WD vehicle. There are a LOT of ORVers so be prepared for people zooming up and down the road with super loud engines. Other than that, free is free.
Month of VisitMay