CNW line abandonment question

I was wondering if anyone knew when the CNW line from Galena Illinois to Platteville Wisconsin was abandoned.
or any other info about this line.

Later Bill

The line from Galena, Illinois to Platteville, Wisconsin was built by the 3’ gauge Galena and Southern Wisconsin Railroad and reached Platteville by January 1, 1875. The Dubuque, Platteville and Milwaukee Railroad had reached Platteville first in 1870 from Janesville. The DP&M became part of the Milwaukee Road. By 1880 the G&SW had been merged into the C&NW. The line was converted to standard gauge in the 1880s. The first segment abandoned was from Galena to Buncombe, Illinois in 1938. Buncombe to Benton, Wisconsin was removed during WW2. Benton to Cuba City was gone by 1973 and Cuba City to Platteville and Madison was gone before 1984.
There is a 5 page article on C&NW’s ridgerunner in the June 1971 Trains, but it hardly mentions your line.
If you want to trace your line on terraserver, here is the northern part on topo. See where it goes and then you can switch over to image. The Milwaukee line runs where it says Acme Mine. Your line runs where it says Abandoned to the junction at Ipswich, and from there north to Madison or south to Cuba City.
http://terraserver.microsoft.com/image.aspx?T=2&S=14&Z=15&X=221&Y=1478&W
This image has Ipswich at the bottom of the V
http://terraserver.microsoft.com/image.aspx?T=1&S=11&Z=15&X=1779&Y=11830&W
The Milwaukee Road pulled out of Platteville in 1975.