Transfer User Security and Files to new machine?

Win2003 Enterprise.

I am replacing a server's hardware. The new server will have the same
configuration in terms of users and files (data disk) but the system
files / OS will be a fresh build. The environment is a Workgroup with
no AD or domains.

Users currently have access to certain folders and shares. Is there
some way to bring this to the new server? I can physically copy files
or I can actually install the old data drive in the new machine, but I
realize this won't bring the user ID's over... or actually might with
ID's I can't use. Is there a better solution that will allow me to
bring it all along vs. having to create new users manually and assign
all the rights again?

Thanks,