Dear RangerRick's Spouse,
To start, I have never fished the Fox Chain, but many of my fellow "Spoonpluggers" have. If you are trolling spoonplugs (sp), you simply have to follow the "guidelines" set forth by Buck Perry. If you and your husband are not familiar with those, I would strongly suggest you purchase his book "Spoonplugging" available from Bucks Baits on the internet. It covers the system of spoonplugging in great detail. That said, I have fished many different bodies of water and the system always works. Here is what you should do:
Troll the shallowest water you can without getting fouled up in weeds. On Marie, I think that would be around 8 feet of water or so. That should be a 250 spoonplug on about 60 feet of line. Troll about 2.5 mph, trying to keep your lure near the bottom. If you do not contact fish at that depth, move to a 200 sp and troll the next area of depth. I think the major breakline or drop off (the depth in which the bottom rapidly drops to a deeper depth)is around 10 feet on Marie. That is a key depth to troll and fish. Once you get deeper than 8 to 10 feet of water, is imperative that you keep your sp on the bottom or as close to the bottom as possible without plowing your lure into the bottom.
Once you find what depth and what area the fish are in you can cast jigs or whatever to catch them.
Again, I recommend that you read anything you can from the late Buck Perry. He figured it out for us.