Starter Will Not Disengage

If you can, take the wires off at the starter. After you disconnect the
battery.
Then hook up the battery making sure the main power wire won't ground
on some thing. Take a test light and check power at both termanls.
You should only have power on the small wire when crancking it.
If you have power there all the time it probley is the relay.If not, it's
the starter.
Let's see what happens.