Starter still being engaged

So I just put a new starter on my V8 302 71 the other got the teeth grinded off. Anyway my starter is still being engaged when I turn the key off. Is this an ignition issue or...?

It could be the starter solenoid sticking. Also make sure the wires are connected correctly on the solenoid, red/light blue stripe wire to the "S terminal and the red/light green stripe wire to the "I" terminal. Also, make sure your ignition switch returns to the run position after starting it.

Ok and I only have one wire going to the starter is that normal?

That depends on what ignition you're running, stock or aftermarket. If it's stock, with points, that would not be normal. What color is the wire and what terminal is it connected to?

Its a black cable on the right side of the solenoid

Sorry with points

Other areas to check is the neutral safety switch and the ignition switch. Could be what caused you original starter to get wiped out.

To check to see if the ignition switch is sticking turn it to the on (run) position (not start) and then you can use a remote switch or take a wire and jump the S terminal on the relay to the hot side (battery terminal) and this will engage the starter. With the ignition in the on position the car should start. Turn the ignition off and see if starter was still running. If not then bad ignition switch.

To check the neutral safety switch find the wiring harness with the 4 pin connector at the back of the block going down to the transmission. You can bypass the switch by disconnecting the connector and using a jumper on the red / blue strip wires on the main harness. Start the car then turn off and see if the starter was still running. If not then bad safety switch.

The large black wire on the right side should go to the starter. There should be two small wires on the front of the solenoid, red with light blue stripe wire to the "S terminal and the red with light green stripe wire to the "I" terminal.

The attachment in post 1 of this thread shows how it should be wired

https://www.7173mustangs.com/thread-alternator-and-regulator-wiring?pid=320622#pid320622