Finally figured out how to turn off the Speed Limit sign on the dash. It's frustrating. I've gone back/forth with having an Onstar subscription, and it works randomly when it feels like it. Most of the time in urban areas where it should be easy to get - it's not there. Dumb. I'm turning it off for good.
For those who haven't figured it out yet, it's on the center dash controls. Scroll to the right to Options, then down to Speed Sign Display. Click it, go to OFF, and then it's gone. Wonderful.
So much better like this!