starter won't stop turning, had to disconnect to stop it.

 

Generally that means that the bendix assembly is hung up in the flywheel or that the start process with the starter relay has a fault. I'd change the starter or the solenoid on the top. It is quite a job to replace a flex plate or flywheel. It is possible that the ignition system has a fault but less likely.

 

I had one that an oil leak dripped onto and shorted it out and did same thing going down the road,is your truck leaking?If not it could be the solenoid.

 

Probably the solenoid on the right front fender. Get a good one, OEM, or maybe Napa.
Some of the cheapies won't hold up. Just changed mine out about a week ago.