Welcome back:
If the starter won't engage, then yes the clutch is most likely the cause. The brake lights sticking was most likely the switch on the top of the brake pedal. I have to be honest, I have never seen someone fix that kind of an issue with a toggle switch.
Now, the clutch pedal has a switch on the top of the pedal. There is a blue wire and a red one. Power from the ignition switch goes through the blue wire to the clutch switch. When you depress the pedal, the switch circuit closes and sends power through the red wire to the starter relay and then the starter. If that switch has been cut, it won't start. If you want to try a test, you could use a jumper wire to make the connection between the two wires at the switch to see if that allows the engine to start. However, if you do that, the engine will crank with the clutch out and the engine in gear, so the car will move. The switch is a safety device. This is only a test and the switch would need repaired if it works. If you try that test, make sure to apply the parking brake and place the transmission in neutral.
I attached a picture of the wiring. Do me a favor. Check under the dash and locate the switch on the clutch. See if the wiring has been damaged in any way. Also, if you can, use a test light to see if there is power to the blue wire when you turn the key to the start position. Here is a link that shows how to use a test light. You can get one for a couple bucks. If there is power but it doesn't make it through the switch to the red wire, place the transmission in neutral and apply the parking brake. Use a jumper wire between the blue and red to see if it will start. This is only for testing.
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
https://www.2carpros.com/articles/how-to-check-wiring
As far as the engine, if it is locked (and that doesn't sound like the issue) chances are you can't unlock it.
Please check what I suggested. It isn't hard and you can ask me anything you want.
Take care,
Joe
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Friday, March 22nd, 2019 AT 8:20 PM