try your local lqk. they ship weekly all around the west/nw.
i found my 05 4:10 sterling w/lsd at one of the local lkq's for 280 with a 100 core. took lsd out of original dana 60 rear end from my 03, then took back the core. now if i could just sell the older lsd and get the stinky thing out of my garage id be set. was told it will work in my sterling so i guess having a backup isn't a bad thing since no one seems too interested in it.
"understeer is when you hit the wall with the front of your car, oversteer is when you hit the wall with the rear of your car, horsepower is how hard your car hits the wall, and torque is how far your car moves the wall."