There is an enhancement in the upcoming 9.5 release which will simplify this process (taking a backup and restoring to an appliance with a different network configuration).
Today, the two best options are either to recreate the rules in the new deployment or to take a back-up, restore to an appliance with the same network configuration, then go through the process for changing the network configuration on that appliance. If you go down the second route, be sure to look up the Knowledge Base articles on best practices for making this transition.