Migrating new W2003 server into W2K domain

I have a new Windows 2003 server that I have not promoted to be a domain controller nor have I put it on our Windows 2000 domain. Should I promote it to be a domain controller before I run the adprep / forestprep and the adprep / domainprep on my windows 2000 domain? Or… Should I leave it as a member server then run the adprep on the Windows 2000 domain then attatch the Windows 2003 member server to the domain and then upgrade it to be a domain controller? Any help would be appreciated.
Thanks