Just to follow this thread up for future reference....
Temporarily disconnecting the other drives and installing xp on a single new drive worked. Then I plugged the old drives back in played around with grub to make it work. It helped having a grub boot floppy to see exactly how grub.conf had to be modifiied. The only surprise for me was that the the new drive had to be "mapped" to the first drive in grub so windows would play nice. All is good...
# grub.conf generated by anaconda
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd1,0)
# kernel /vmlinuz-version ro root=/dev/sdb2
# initrd /initrd-version.img
title Fedora Core (2.6.14-1.1644_FC4)
kernel /vmlinuz-2.6.14-1.1644_FC4 ro root=LABEL=/ rhgb quiet
title Fedora Core (2.6.11-1.1369_FC4)
kernel /vmlinuz-2.6.11-1.1369_FC4 ro root=LABEL=/ rhgb quiet
title Windows XP x64 Pro
title Windows XP Home
map (hd0) (hd2)
map (hd2) (hd0)