Finally got this working, Much thanks to William Lam.
Didnt need to follow http://www.virtuallyghetto.com/2011/05/semi-interactive-automated-esxi.html exactly with 5.5. The boot options are already written to the esxi_installer.log file by the installer. But it's written multiple times, so gotta do 'grep blah blah | head -1' to get just the first instance of the boot options. Next steps will include setting up all the vmk interfaces based off the nodenumber.
So, my ks.cfg looks like:
root@deb7:~/esxiso# cat ks.cfg
accepteula
rootpw asdf1234
install --firstdisk --overwritevmfs
reboot
network --bootproto=static --hostname=tempname001 --ip=1.1.1.251 --gateway=1.1.1.254 --nameserver=1.1.1.250 --netmask=255.255.255.128 --device=vmnic0 --addvmportgroup=0
%firstboot
sleep 60
grep 'Got boot options' /var/log/esxi_install.log | head -1 | sed -e's/.*node=\([^ ]*\).*/\1/' >> /vmfs/volumes/datastore1/nodenumber.txt
NODENUMBER=$(grep 'Got boot options' /var/log/esxi_install.log | head -1 | sed -e's/.*node=\([^ ]*\).*/\1/')
esxcli system hostname set --fqdn=mptc-esx${NODENUMBER}.ps-msite.com
#enable ssh & tsm
vim-cmd hostsvc/enable_ssh
vim-cmd hostsvc/start_ssh
vim-cmd hostsvc/enable_esx_shell
vim-cmd hostsvc/start_esx_shell
# rename local datastore to something more meaningful
vim-cmd hostsvc/datastore/rename datastore1 "$(hostname -s)-local-storage-01"
#disable ipv6
esxcli system module parameters set -m tcpip3 -p ipv6=0
# backup ESXi configuration to persist changes
/sbin/auto-backup.sh
# enter maintenance mode
esxcli system maintenanceMode set -e true
# copy %first boot script logs to persisted datastore
cp /var/log/hostd.log "/vmfs/volumes/$(hostname -s)-local-storage-1/firstboot-hostd.log"
cp /var/log/esxi_install.log "/vmfs/volumes/$(hostname -s)-local-storage-1/firstboot-esxi_install.log"
root#deb7:~/esxiso#