Do you need the contact information for Straits Scuba? They are a great group of guys. There's not much diving out of Cedar River (unless you want to pay a bunch) but if you're looking for some wrecks - they're 25 miles away in Menominee (M&M Diving). Quite a few nice wrecks there. Not at all like diving Mackinaw (low viz, dark, etc) but we usually dive them every week (when we're not going to Mackinaw, Munising or Sheboygan, WI). Fayette Park is nice but a ways out of the way if you're headed to Mackinaw. If you decide to go, let the guard know you are a diver and they will let you park down by schlag beach. It's a nice easy shore dive but runs out of scenery quickly (into sand). The beach is all rock and it's rare to run into anyone there.
The legend of Poverty Island also includes the chests of gold that went missing but don't bother to look for them, they're in my back yard buried under my highly guarded crops.