When did Minoru Suzuki start being the murder grandpa we all know and love?

I’m guessing it happened during the early 2000’s? I’ve found matches of him with the shaved head as early as 2005. Does anyone know when and why he changed up his look? I apologize if this is a dumb question or if the answer is well known already, I only started watching NJPW on a consistent basis a couple years ago so I’m a bit new to say the least lol