I tried adding the following to a patch but after I boot up the newly patched ISO image it's not changing the default network interfaces file.

iface="eth0"
ipadd="192.168.1.2"
subn="255.255.255.0"
gatew="192.168.1.1"

echo "#The loopback network interfaces" > /etc/network/interfaces
echo "    auto lo" >> /etc/network/interfaces
echo "    iface lo inet loopback" >> /etc/network/interfaces
echo " " >> /etc/network/interfaces
echo " " >> /etc/network/interfaces
echo "#The primary network interface" >> /etc/network/interfaces
echo "    auto ${iface}" >> /etc/network/interfaces
echo "    iface ${iface} inet static" >> /etc/network/interfaces
echo "        address ${ipadd}" >> /etc/network/interfaces
echo "        netmask ${subn}" >> /etc/network/interfaces
echo "        gateway ${gatew}" >> /etc/network/interfaces
echo "        dns-nameservers 8.8.8.8 8.8.4.4" >> /etc/network/interfaces

Any suggestions? 

Thanks!