Best way to migrate SBS 2003 to new server and subdomain to parent

Microsoft Windows

I inherited an office network with a single SBS 2003 server, placed on a
subdomain, i.e., subdomain.company.com. The subdomain is unnecessary--we
have only one domain on our network and only one server. We're replacing our
old server with a new one, and I'm looking for a way to:

(1) Get rid of the subdomain without loosing AD and Exchange.
(2) Migrate SBS 2003 to the new server without loosing AD and Exchange.

Seems ADMT might work for (1), and a swing migration (www.sbsmigration.com)
might work for (2). However, I'm not familiar with either method and I'd
like some input before I dive in.

So, what's the best way to move SBS to a new server and move a subdomain to
its parent, all while keeping AD users and Exchange mailboxes intact?
Bennett
Are you suggesting that the SBS server is setup as a subdomain of another AD
domain/forest

or

That there is a subdomain setup with the SBS Forest/Domain?

Cris Hanna [SBS-MVP]
We have only one AD domain/forest, subdomain.company.com. I think the person
who set it up many years had grand plans of a massive network and "subdomain"
was supposed distinguish office locations. Don't need that now and our one
and only server is server.subdomain.company.com. There's nothing at the
company.com level.

If our server was just plain ol' Windows Server 2003, I could just install
the new server on company.com and use ADMT to migrate subdomain.company.com
to company.com. But with SBS's trust and child domain restrictions, I'm
thinking that I'll need to:

(1) create a temporary Windows Server 2003 as DC for company.com,
(2) use ADMT to migrate,
(3) install the new SBS server on company.com,
(4) and ditch the temporary DC and old SBS server.

Will that work and thus solve both my problems of upgrading the SBS server
and migrating AD?
in either case your AD, ending in .com, would be incorectly named.

do yourself a favour and migrate the domain to a sensible top level like
.lan.
of view. Internal domain name should not affect users. To change name you
would have to follow steps of migration / reinstall. Is it worth the effort?
Well, we're moving SBS to a much-needed new server, so I already have to
migrate and reinstall. Also, from my understanding, I can't have 2 SBS on
the same domain, so I need a temporary DC to swing. Since I'm already
creating a temp DC and installing SBS on the new server, I thought it would
be a good time to get rid of this unnecessary subdomain and move everything
to the empty parent.

If what I suggested below works, seems the only extra step I have is a
relatively minor ADMT. However, I remember reading something about SBS needs
to be present before other DCs, so that might negate my whole 4-step plan.
Know anything about that? Will my 4-step plan work?