If you are just doing this once, you might want to rent a wire locator from a local Irrigation Supply House. The clicker does work but I have a Progressive Electronics 521 Wire locator and
have found valves on the beach lost from Hurricanes. This is the type they usually rent. You just start at the Controller and follow the dead spot between the two tones. As far as the wires, make sure they have a wire spice on them, but don't bury them in the valve box.
Richard Kersten
S&R Sprinkler Systems and Landscaping, Inc.
Destin, Florida