Need Advice on Upgrading Exchange 2003 Standard to Exchange 2003 Enterprise w/Clustering

I have called M$ on this issue, but wanted to make sure if anyone else here had done this before or not, and what to look out for.  I have a very simple Exchange setup.  I am running 2003 w/SP2 applied on an old Dell 6650.  Windows 2003 Standard w/SP2 is the OS that I am running on.  OWA runs on the same box and not a front-end server.

Fours years later, I now wish to do the following:
1) Upgrade the site to Exchange 2003 Enterprise with a two-node cluster.  I am thinking I can do this, by introducing a new exchange server into the existing site running Exchange Enterprise and Windows 2003 Enterprise server.  I can then make the new server the site master and setup the clustering accordingly.  After that, all I should have to do is to pull the mailboxes over to the new server.
2) Establish a front-end server for OWA services.  I am thinkg that I can set the current Exchange Server running standard edition as a front-end server (after I move the mailboxes to the Enterprise server of course).  

M$ said that I should be able to accomplish what I want by the aforementioned plan, but I wanted run it by the experts on this site in case I am missing something.  I just can't believe it going to be this straight-forward.

Thanks