Bob, what was the length of your slip/well?
Side note:
On Lake Michigan they are called slips, Lake St. Clair I remember they were called wells. I guess.
It was a 70 ft. well, they are hard to come by. Most of the indoor wells at Mac Ray's are attached to condo's which are privately owned. So finding one probably wouldn't happen by talking to the marina, but asking around the boat dealers down there would be a better tactic.
Sassy's for winter storage is probably your best bet.
There are a lot of places along the st. clair shores area, they call it the nautical mile.
Sorry but I don't know any of the names over there. It's basically the area from Mac Rays going south from there.
Are you looking for just winter storage or a place for the summer as well?
I think for summer Algonac Harbor Club is pretty nice (were we are) but the wall we are on I know is full, they have dockage on the "other side" of the main building, they might have room over there, or maybe dockage on the wall by the restaurant. It's nice with a pool and tiki bar / restaurant right on site. Nice central location to get to the St. Clair River or the lake.
If your pockets are deeper the Old Club on Harsens island has dockage for larger boats, I was told they dock up to 100 ft. Also there is a marina out on the middle channel on Harsens island, I don't recall the name but I would bet they have openings as I think it might be access by boat only, but not sure about that.