The Official Cert Guide for CCNP Route said GRE is the only tunnel you need to know for the exam.
This has both IPv4 and IPv6 tunnels. The top is OSPF multi-area and the bottom is EIGRP. Flat-1 gets the simulation out to my redirect tftp commands to create text files.
I used the interfaces not loopbacks for the tunnel. Static routes connect the ends of the tunnel not EIGRP or OSPF.