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Route a print server

I am asking this community for some advice on routing using a CentOS 7 server. This situation is as follows:

I have an external print server (let’s say it’s on subnet 10.0.0.0/24 with an IP of 10.0.0.13).
I have a CentOS 7 server with external IP of 10.0.0.5 on eth0 and an internal IP of 198.162.0.130 on eth1. This internal NIC is connected to a printer that has an IP of 10.0.0.4.

Here is what I have tried:

1) Enabling ip forwarding

echo net.ipv4.ip_forward=1 >> /etc/sysctl.conf

2) Adding a route

ip route add 10.0.0.4 dev eth1

3) Attempted adding a rule

ip rule add nat 10.0.0.4 from 10.0.0.13

(CentOS responded that this command is deprecated)

4) I’ve attempted a lot of things using shorewalld, firewalld, and iptables.service. Right now I have iptables service enabled and have issued the following commands (policy on all chains set to drop, exclusions being accept on port 22 and 9100)

iptables -A FORWARD -p tcp –dport 9100 -m conntrack –ctstate NEW,ESTABLISHED -j ACCEPT
iptables -A FORWARD -p tcp –sport 9100 -m conntrack –ctstate ESTABLISHED -j ACCEPT

(Including variations on these commands that include specific IP addresses and interface names).

5) I’ve even modified the network-scripts for my eth0 file to include the IP address of the printer (note printer and print server are on the same subnet).