In the EIGRP and OSPF sim section I created a GRE tunnel simulation that used the links between the routers instead of the loopbacks. For completeness I build this one using the loopbacks as the tunnel endpoints.
This simulation has IPv4 and IPv6 tunnels. Flat-1 connects to the real world for TFTP. the link between iosv-1 and iosv-2 is not in EIGRP. I have only static routes for the loopbacks on either end. I changed up the loopback addresses to /128 from my usual /64. Tunnel 0 is IPv4 and Tunnel 1 is IPv6. Tunnel endpoints are the loopback interfaces.