An interesting article from space dot com re. using the upper stage of the SLS as a deep space station.
This was suggested many times for the Shuttle ET, but never attempted. They should be able to do something similar to get an empty first stage into orbit. Equip it with hatches and mounting fixtures and launch it without a second stage, or with a simple propulsive stage to push it the rest of the way into orbit and stabilize it for further assembly. It would probably take more work afterward to turn it into a space station, but it'd be much bigger.
Of course, both options would also cost a few billion dollars even before modification, just for the SLS launch...
