restricted groups for local admin rights

Hi all,
2003 server using gp for windows xp workstations
My goal is to use restricted groups under gp to add several users to the
local workstation administrator group.
I have read several articles on how to do it but it is confusing to me.
My questions:
can I use my current custom gp and just add the restricted group there or
will it override the other restrictions in the gp for the users that I add to
the restricted group?
Can you give me the steps to set this up. (when I tried the other articles
steps I couldn't browse to the local administrators group to add it as the
restriction point. In other words, I don't know how to tell the restricted
group to be related to the local admins group)
Also, under restricted gp the icon has a lock picture on it. What does this
mean?
Sorry, the restricted groups process hasn't clicked for me yet? I know I
could use this for other things also but just can't seem to understand the
process.
Thanks in advance for any help,
Sher


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