Got the major server software installed on thebrain last night. Copied all the data over, including my user directory - all 2.1 GB of it. Switched to the new system this morning; had a problem with the CVS server that turned out to be a misconfiguration in xinetd. The new system is in place and running, and even seems a bit speedier than the old one, no doubt due to the RAID.
I've moved the hard disk out of the old one to the new one just in case I missed copying something over. There's a new hard disk in the old machine, which is going to be recycled as a Gentoo development box.