GUI Script as second user / admin

I’m in the middle of a large script, which already gets an administrator username/password combo early on.

Now, I’m trying to use the gui scripting to manage a few preferences. I discovered that I could run “System Preferences” as the admin, using “do shell script” and, the padlock is opened by default; but, system events doesn’t seem to want to deal with this window at all. It actually starts a second instance of System Preferences (with my own account; and, of course with the padlock locked).

Is there any way to get System Events to talk to a window “owned” by another user like that?

I know that I can start System Preferences the normal way, click the locked padlock, and use SecurityAgent to keystroke the password; but, ideally, I’d like to have a less distracting way (ie, no extra password windows popping up).