It's beyond the halfway point, but Casper, WY may be a good stopping point. You may want to post this question on the Road Trips forum for input. The folks on there are very good with routes, etc. We typically fly into an area and go from there.
The way I see it, you really only have 1.5 touring days. You would have enough time to see Rushmore and Custer State Park, but just keep an eye on your weather. I would not make the drive if there's any snow predictions. Many of the roads in CSP are very winding so you would not want to be driving them in poor conditions.
How do I get to the Road Trip forum you speak about?
To see the Road Trips forum, you need to be on the full site, not the mobile site.
Here's a link to the Road Trips forum:
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