1970 Duster starter wire question.

So I plugged a non original wire onto the slide on connector pictured between the 2 big lugs. The wire runs up to the relay. There is another owner applied red wire that I have to run to the + on the battery for the car to power up. How is this relay suppose to get power properly? What color wire? The previous owner had a homemade anti theft system and this is how he did it.