There is camping in the area, but not a lot of water on Wild Bill. Look up Lake Mary Ronan, Flathead Lake, along the North Fork of the Flathead River (North of Columbia Falls), or follow the road to Libby and there are lakes that have camping. Along Hungry Horse Reservoir also has camping. Also could go through the Swan range South East of Bigfork. May be able to get camping in Glacier National Park, but they fill up quick.
If you get a current MY Gazetteer it will give you a good idea of what's available and where. The Forest Service also has maps that may help you avoid the tarmac.
Sorry I can't give you better info, but it has changed a lot since left and came back. We used to be able to plug for bull trout in the river and keep them, not to mention snagging salmon and watching eagles at Apgar.