I recently just got a 79 Celica GT and I am thinking about trying to add a remote kill switch, since I think it would be best since, I can hid the relay somewhere out of sight behind something that you need at least 15 minutes and some tools to take apart, and I can keep the switch on me.

I googled best way to wire a kill switch onto a classic car, and I found a video about a guy hooking up a normal switch to the distributor.
They spiced their switch between the battery terminal. What I want to do, is splice in a relay with a remote control.

I found a 12V 40A relay on amazon for $20 but I realized that relays need power to work. I don't think I can just connect the positive wire like on a normal switch.

Do you think I can connect the positive wire to the relay power input with a ground wire to the relay negative input from somewhere else and just connect the output how I need to. Or do you think that will cause issues?

I am sorry if I sound stupid.

Thanks for reading my thread.