According to the latest information available online, the boat ramp named Big Muskego Lake - Big Muskego and Bass Bay is located in Wisconsin, specifically at latitude 42.89572144 and longitude -88.08737946.

This boat ramp provides access to Big Muskego Lake, a 2,260-acre freshwater lake located in Waukesha County. The lake has a maximum depth of 34 feet and is known for its fishing opportunities, especially for largemouth bass, northern pike, and panfish.

The Big Muskego Lake boat ramp is a concrete ramp that is reportedly wide enough to accommodate multiple boats launching at the same time. However, there is no specific information available online regarding the exact width of the ramp.

As for the types of boats permitted on the water, it appears that there are no restrictions on the kind of watercraft that can be launched from this boat ramp. However, visitors are advised to follow all local regulations and safety guidelines.

Overall, the Big Muskego Lake boat ramp provides convenient access to one of Wisconsin's largest inland lakes, allowing boaters and anglers to enjoy a variety of recreational activities on the water.