I had this car running before, but one day, when I tried to turn it on it would crank but wouldn’t start. I kept trying until it finally ran but now it wouldn’t stop cranking. I wasn’t too far off from home so I drive it home like that. When I got home it wouldn’t turn off until I stalled it. After that it didn’t crank at all. So we replaced the engine harness, under dash harness, starter, distributor, both fuse boxes. And fixed the ecu. Now the only way it’ll crank and start is if we put a wire from the main power cable to the starter. It won’t crank with the ignition. I even have a JDI push start ignition and it won’t crank with it either. I don’t know what to do now.

 

It might be the ignition switch harness.

You really need to get with a good electrician who knows how to diagnose the break from the ignition switch to the starter and check for continuity once you find where it's losing the signal you should be able to figure out what's needed. Maybe it's a wiring issue somewhere else on a harness you haven't checked.