2000 Buick Century starter cranks when battery connected

[Jason Herre]

I am working on my sons 2000 century and he was recently stranded with a no crank no start.
I determined that the starter was bad and replaced it. Everything went well until I reconnected the battery and the engine started cranking. I removed and reinstalled several times and even bench tested starter. I even tried installing starter without connecting small actuator wite and it still cranks the second I connect battery. HELP!!

 

[MelsRegal]

Did you look in the owners manual for the location of a starter relay that may be stuck in the on position