where is the other end of the black wire connected, does it go to the push button? Maybe get a long wire and connect it to the black wire and hold the other end near the electrode and see if it sparks. Don't bother turning on the gas as you're not trying to burn yourself, just seeing it you can get a spark working. If it sparks there then you know the igniter still works and you can start looking for a bare metal part of the stove to attach it the black wire to. unless of course the black wire is the one with the current on it. You can test that by holding a bare end of it near a burner but not near the electrode and see if it sparks.
