Best way to reset a duplicate node

Somehow along a couple computer upgrades and moves I’ve ended up with a cloned machine and thus a cloned node. What’s the best way to ‘reset’ a node of its ID, etc. Oddly, the synching seems to be working still for many of the shared folders—I’m not sure how.

If you delete the key files (see, the ID will be automatically reset without touching the rest of your local configuration.