Do you still have the old starter? If so, re-install it and see if the engine cranks over. The new starter may be bad or mis-aligned to where it is getting bound up and not able to turn. Maybe just remove it from it's mounting point and hit the key to make sure it actually spins.......or, use a remote starter switch that you connect between the Solenoid terminal of the Starter and the 12v main power wire at the starter.