This repo is an example of how to run an ExEx on the TelosEVM 2.0 version (or many, you can add as many as you want to a single node).
For proper examples of various use cases, see the examples repo from Paradigm who are the creators of reth.
Notice that this main.rs is a copy of the telos-reth main.rs file, with the addition of .install_exex("Example", exex::exex_init) to the builder. As the telos-reth repo gets updated, this main.rs file may need to also be updated with those changes.