if you have specific password for all wksta's on your network... like every wksta has "mydomainwksta" as password that would be easy... with something like su.

anyway, easiest would be setting up a script on some of your servers that reads an ini for all workstations that do not have domain users as the wksta-admins and add them.
that script has a scriptlet in logonscript that checks if user is in local admin and if not, adds the entry to the ini.

ofcourse every domain-user must have access to this ini.

one option is to create similar script which crawls arounds your net immediately and changes all the wksta's found but that way you never have quarantee of getting to all machines.

now, the decision is yours, which way you want to go?
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