Winders previously pleaded not guilty after being arrested and charged with murder in December 2015.
The 65-year-old Taiaroa was shot and killed as he operated a stop-go sign at roadworks in Atiamuri three years ago.
“Mr Winders, you are convicted of murder. You are now subject to the three strikes law,” said Justice Toogood.
“Murder carries with it a mandatory period of life imprisonment, with a minimum serve period of 10 years.”
Winders will be kept in custody at the High Court in Rotorua until early November.
“George was so much more than a victim of a crime. He was a husband, a father, a grandfather, a work-mate and friend,” said spokesperson for the Taiaroa family, Ani Mikaere.
“Nothing can bring him back, but his legacy will endure. His whanau are committed to moving forward, to living lives that he would be proud of and to honouring his memory every day.”