Linux Simple NAT
I'm trying to explain how a simple network can share a connection using a linux router. The same router can also serve file sharing, mail server and other stuff to the network.
1) load the ipt_MASQUERADE . Depending on the distro, this could be built in, already loaded or not available. Try continuing even if it fails.
2) Be sure to flush all the rules in iptables. You can apply yours after you see NAT is working.
iptables -F; iptables -t nat -F; iptables -t mangle -F
3) Enable ip_forwarding in the kernel
echo 1 > /proc/sys/net/ipv4/ip_forward
4) Forward your ips to the one on eth0
iptables -t nat -A POSTROUTING -s 192.168.10.0/24 -j SNAT -o eth0 --to 184.108.40.206