There is a support document to install but not how to UN-install.
How To: Install an Esri StreetMap Premium license file on ArcGIS servers without ArcGIS for Desktop
Hi Bill,
Sorry for the late response! You have probably already found the answer, but here are the steps (for Windows).
You can use the same DataLicInstall utility in the command prompt to install, overwrite, or uninstall StreetMap Premium licenses. Run the command datalicinstall.exe -h for more information about the utility.
To uninstall an .sdlic license file:
To override an .sdlic license file with another license file:
Hope this helps!
-- Rachel